What is the mystery of "Gypsies" in China?

There is a Xue Jiawan in Yongdeng County, Gansu Province. The residents there have been wandering for generations, making a living by divination and palm reading. Some people suspect that they are descendants of Gypsies who emigrated to China. Xue Jiawan is located on the hillside, and there are 144 households in the village. The land here is barren and vast, and it still maintains the custom of wandering. Farming in the village for half a year and traveling around for half a year. Their divination and divination skills will never be revealed. Xue Jiawan people also speak a argot called Shao Sentence. Shao sentence is only used when there are outsiders present and it needs to be kept secret. These cultural characteristics of Xue Jiawan people have aroused the interest of many scholars, who have come to investigate.