I learned from news in 2012 that such a group of people were living in a mountain so I remembered it. I had nothing to do in July, 2016, so I was available enough to go to Yunnan, paying them a visit and also checking if I can do documentary there. I spent one week looking for them，and then tried shooting some videos. Well, it seemed pretty good and happy; I thought it could be a good documentary so I kept on working and then finished it.