Forward-private dynamic searchable symmetric encryption (DSSE) with efficient search

A method of searching encrypted files includes a client computing device selecting a specific keyword to search a plurality of encrypted files stored at a server computing device and if the specific keyword has not been previously used to search the plurality of encrypted files, the method further includes using an encrypted keyword index stored at the server computing device to identify one or more encrypted files of the plurality of encrypted files that contain the specific keyword based upon keyword-file relationships stored in the encrypted keyword index. The method also includes, storing the keyword-file relationship for each of the one or more encrypted files that are identified as containing the specific keyword in an encrypted dictionary at the server and during a subsequent search, if the specific keyword has previously been used to search the plurality of encrypted files, the method includes using the encrypted dictionary and the encrypted keyword index stored at the server to identify one or more encrypted files of the plurality of encrypted files that contain the specific keyword based upon the keyword-file relationships for the specific keyword previously stored in the encrypted dictionary