Dunhuang documents were discovered on May 26th (1June 22nd, 900) in the 26th year of Guangxu in Qing Dynasty by Taoist Wang who was guarding the Mogao Grottoes. Without accurate statistics, it is generally estimated to be around 40,000 to 50,000 pieces. When Wang, the Taoist priest guarding the Mogao Grottoes, was working in Cave 16 with a copy of Yang's surname, Yang inserted the paper twist for smoking into the wall crack near the inner north wall of the cave entrance, but the paper twist fell into the crack. Wang and Yang suspected that there might be another hole in the wall, so they dug the wall at night and found a hole (hole 17) filled with bundles of ancient cultural relics and suicide notes. Since then, ancient suicide notes that have been sealed for nearly a thousand years have reappeared. 1944 was found in the statue of the underground palace in Mogao grottoes, and 1965 was found in the site in front of Mogao grottoes 122 grottoes. The first few years after the discovery of Dunhuang suicide note did not cause a sensation. 1907, British Hungarian A. Stein arrived in Dunhuang during his second expedition to central Asia. With the help of Jiang Xiaowan, a translator, Wang Daoshi's ignorance and devotion to religious belief were used to defraud 24 boxes of Dunhuang suicide notes and transport them back to Britain. Stein's Harvest immediately caused a shock in the west, and treasure thieves flocked in the name of "explorers". By the cultural thieves of Britain, France, Japan, Russia and other countries (Stein, Pelliot, Otani Expedition, Odenburg, etc. ), many people have lost their overseas life, and most of them are hidden in the London Museum Library, the National Library of Paris, and the Leningrad Branch of the Institute of Asian People's Studies of the Soviet Academy of Sciences. Coupled with scattered migration, Dunhuang materials are currently concentrated in Britain, France, Japan, Russia and China, and scattered in Germany, Denmark, Sweden, the United States, India, South Korea, Hong Kong and other countries and regions. In China, Chinese papers are mainly collected in Beijing Library, and Dunhuang Tomb Raider Record and its supplement have been compiled. Tibetan papers are mainly collected in Gansu Provincial Library and Dunhuang County Cultural Center.