Abstract: In the traditional keyword-based searchable symmetric encryption technology, the keyword set is usually generated by the keyword extraction algorithm, so that the content and quantity of the keywords are limited by the keyword extraction algorithm. Therefore, in the keyword-based encryption search system, in addition to the keyword set generated by the system at the time of initial construction, the user cannot search for other related contents, thereby limiting the application of the encryption search technology. In view of the above problems, this paper proposes a flexible accuracy-controllable searchable symmetric encryption (FASSE) that supports flexible and precise control. By flexibly generating keywords and indexes generated by document summary during system operation, the dependence of the keyword collection effectively improves the flexibility of the encryption search technology. FASSE provides three basic searches, namely one-shot search reinforcement search and filter search, which respectively correspond to the user finding the keyword record in the dictionary only once, not finding the keyword record in the dictionary and only using it once. The search finds records or three search cases where keyword records are found in the dictionary and abstract multiple times. At the same time, the system also combines three kinds of search to design a fuzzy reinforcement search to further enhance the practicability of the system. The specific implementation language of the FASSE program is the Java programming development language and the final experiment shows that FASSE averages 114.26 ms in searching each paper in the https://eprint.iacr.org/complete/ paper dataset.