Biblio
Searchable encryption is a new developing information security technique and it enables users to search over encrypted data through keywords without having to decrypt it at first. In the last decade, many researchers are engaging in the field of searchable encryption and have proposed a series of efficient search schemes over encrypted cloud data. It is the time to survey this field to conclude a comprehensive framework by analyzing individual contributions. This paper focuses on the searchable encryption schemes in cloud. We firstly summarize the general model and threat model in searchable encryption schemes, and then present the privacy-preserving issues in these schemes. In addition, we compare the efficiency and security between semantic search and preferred search in detail. At last, some open issues and research challenges in the future are proposed.