Nine days and nine nights will take you to crack the secrets of billions of dollars.

This is an important yak trading market in Northwest China. Carts carrying yaks from the pastoral area gather here one after another every evening.

This man, named Yu Genlai, is one of the few big cattle collectors here, but when he first came here 10 years ago, no one took him seriously.

Wu Tiejun, a yak dealer: "We have known each other for more than ten years." In the past, he couldn't buy five or six cows a day, but now it's too late for us to curry favor with him. He now needs 400 to 500 cattle a day, which is quite a large number in our industry.

September and October are the peak season for yaks out of the fence, and dealers are waiting around the clock, eager to try, as long as yaks are pulled into the market.

Reporter: what are you looking at?

Yu Genlai: look at whether the cow is fat or thin and whether there is much meat.

Reporter: why are you in such a hurry?

Dealer: it's time to do business. If you're late next year, the cow won't be yours.

The local yaks are so popular that buyers not only have to do it quickly, but also bargain with each other on their sleeves.

Yu Genlai: they don't understand what our price is.

Interviewer: the next person knows. Why?

Yu Genlai: if you know that, you will raise the price, which is definitely higher than mine. I will give you 20 yuan per jin, and he will definitely give 21 yuan per jin to compete with each other.

The transaction lasted until seven or eight o'clock the next morning, and Yu Genlai spent the night in the market. Strangely, he didn't buy a cow.

Yu Genlai: I don't know what's going on in the market without kissing (since). We need to know how many goods there are. Because the competition is too fierce, because the price is high, there is no competitiveness in the market.

Yu Gen will buy more than 30,000 yaks in the coming year, and even if there is a difference of 10 cents per jin, it will bring him a loss of 400,000 to 500,000 yaks. therefore, it is very important to find out the yak market. Next, Yu Genlai will go deep into the pastoral area to buy yaks from the herdsmen's homes, which is the birthplace of his wealth, and there have been a lot of unexpected situations along the way.

It was the first day that Yu Gen came to the pastoral area to buy yaks, and along the way we came across a yak herd that was changing the market.

Nomadic migration is the life style of Qinghai grassland herdsmen from generation to generation.

In early autumn, it snowed in some high-altitude areas of Qinghai, and herdsmen packed up all their belongings and moved from summer pastures to relatively sheltered winter grasslands.

This herdsman is driving more than 200 yaks to migrate, which can be counted as a big family here, and the chance encounter with them made Yu Genlai very excited.

Yu Genlai: look at the cow, see how big the cow is, and discuss the price with him.

Reporter: do you have a crush on this cow?

Yu Genlai: well, this cow is very good.

Unexpectedly, our actions unexpectedly aroused the dissatisfaction of the herdsmen.

Interviewer: bombard us, right?

Yu Genlai: go this way, come on!

Interviewer: what happened to him?

Yu Genlai: he was angry. He was angry. He was really angry. They drove the cow back.

The local guide told us that during the transition, the herdsmen had to keep driving in order to keep the yaks on the planned route, but our sudden appearance just stood in the way of the cattle, and the disturbed yaks became disobedient.

The local guide Dan Zengqiang said: driving cattle is very hard. You are in front of the cow. When the cow sees a person, he won't leave. Do you know?

Yu Genlai, a native of Fujian, was forced to come to the homes of grassland herdsmen to buy yaks in 2005. Now, 10 years later, the southerner still has trouble buying cattle in the pastoral area.

Local guide Dan Zeng sharp measures: customs are different, you do not understand, conflicts often occur.

Yu Genlai: he was unhappy when we didn't get through.

Over the past two months, Yu Genlai has collected an average of 500 yaks a day, and he feels a lot of pressure.

Yu Genlai: we have come a long way to buy your cattle.

Local guide Dan Zeng sharp measures: cattle do not sell, others do not sell, angry do not sell, then let's look for it again.

Reporter: don't sell if you are angry? Give him no money?

The local guide once increased sharp measures: no, the relationship is good, send it to you, give you a head is no problem, the relationship is not good, how much money he will not sell to you.

Just arrived in the pastoral area, encountered a bad start, Yu Genlai's heart cast a shadow, the next acquisition road, what will be waiting for us?

Our car climbed many mountains and climbed all the way, and more than three hours later, the car broke down.

Yu Genlai: the pot is boiled, it is very hot, the mountain road is easy to boil, this road is very steep, very bad, often boil.

The pastoral area is so sparsely populated that it is not necessary to encounter a car passing by in a few hours. Cell phone signals are often sporadic, and it takes a lot of trouble to make a phone call for help.

Reporter: did you get through to the phone?

The local guide Dan Zengxiaozuo: got through.

Interviewer: what should I do?

The local guide increased his sharp measures: he said he couldn't come all of a sudden, so what should he do?

Local guide Dan Zengjiezuo: how long will it take him to come from there?

Reporter: an hour and a half.

Yu Genlai told reporters that since he began to buy yaks in pastoral areas, he had encountered many more difficulties than this, and even his life had been threatened, but he never wanted to back down.

At the age of 22, Yu Genlai came to Qinghai from his hometown of Gutian in Fujian Province, pushing bicycles to peddle local specialties. 15 years later, his life did not improve much.

Yu Genlai: there is no way to go home, can not see the villagers, came all the way here, you said I went back empty-handed, villagers, neighbors look down on you, including parents look down on you, others can go out, why do you go home empty-handed?

Yu Genlai longed for a prosperous return to his hometown, but it was not easy for him, who had only studied for three years.

In 2005, this kind of dry meat jerky made Yu Genlai see the hope of turning around. This traditional delicacy from the herdsmen's family was rare in the market at that time. Yu Genlai smelled the business opportunity and raised more than 100,000 yuan to build a yak jerky processing plant in Xining.

Yu Genlai's yak jerky is not worried about selling, but because of lack of money, every time I buy yak, I can only buy two or three yaks, and only when the products are sold can I have the money to buy cattle again. Production in the factory is on and off, and everyone thinks that this small business is not a big deal. But a year later, relying on a wealth plan, Yu Genlai received 3500 yaks a year, with annual sales exceeding 5 million yuan.

The tents of nomadic herdsmen are hidden in the endless mountains, and sometimes it takes several mountains to encounter one or two households. In 2006, Yu Genlai came to the pastoral area to find herdsmen who were willing to cooperate with his wealth plan.