A file system program that controls a processor to create an attribute information area in which a registered keyword as metadata of the data attached to the file; wherein the file system program comprises: a file access control module that controls access to the file; and a file search module that searches for the file using an inputted keyword, wherein the file search module comprises: an attribute information search module that searches for a file by comparing the registered keyword and the inputted keyword; and an entire document search module that searches for a file by comparing the entire file and the inputted keyword, and wherein the file access control module comprises an. attribute information change module that changes the registered keyword based on a result of the search by the entire document search module.