1), Superstar Electronic Library: The collection of e-books is rich in content, including more than 50 disciplines such as classical theory, philosophy, social science, economics, language, literature, mathematics, physics and chemistry, biology, industrial technology and computer. At present, there are 800,000 kinds of Chinese e-books, 3 million papers and more than 400 million full-text industries. And it is constantly updated and supplemented every day. 2) Scholar's House Digital Library: It mainly includes new books published after 1999, and its collection is more than half of the new books published every year in China. At present, it has150,000 books, with a considerable number and complete disciplines. 3) Full-text Database of China Academic Journals: The products of this database are divided into ten photo albums: Science and Technology A, Science and Technology B, Science and Technology C, Agriculture, Medicine and Health, Literature, History and Philosophy, Politics, Military and Law, Education and Social Science Synthesis, Electronic Technology and Information Science, Economy and Management. The album is divided into several topics, *** 168 topic. 4) VIP Chinese sci-tech periodical database: According to China Library Classification, all documents are divided into eight volumes: social science, natural science, engineering technology, medicine and health, agricultural science, economic management, educational science and library information. These 8 albums are subdivided into 36 topics. 5) Features of Wanfang Digital Journals: At present, more than 70 kinds of science, engineering, agriculture, medicine and humanities have been collected, and more than 2,500 kinds of core journals of science and technology have been realized online. Periodicals included in the system include seven categories: basic science, agricultural science, social science, philosophy, politics and law, medicine and health, education, literature and art, economy and finance. How to use VIP, Wanfang and Superstar (1), and the method of "advanced retrieval" in VIP Chinese sci-tech periodical database: open VIP database, click advanced retrieval, enter keywords, authors, classification numbers, institutions and periodical names, expand the retrieval conditions, such as time conditions, professional restrictions and periodical scope, and then click retrieval. 2) The method of "advanced retrieval" for full-text database of China academic journals: Open China HowNet, click Advanced Retrieval, enter full-text database of China academic journals, input retrieval control conditions, such as publication time and annual support fund of journals, and then input content retrieval conditions.