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With the advent of cloud computing, data owners tend to submit their data to cloud servers and allow users to access data when needed. However, outsourcing sensitive data will lead to privacy issues. Encrypting data before outsourcing solves privacy issues, but in this case, we will lose the ability to search the data. Searchable encryption (SE) schemes have been proposed to achieve this feature of searching encrypted data without compromising privacy. This method will protect both the user's sensitive information and the ability to search for encrypted data. In this article, we review the various SE designs. In this review, we present the classification of SE designs: symmetric searchable encryption, public key searchable encryption, and search attribute-based encryption schemes, and then a detailed discussion of SE designs in terms of index structure. And provide search functionality. There is also a comparison of SE design analysis in terms of security, performance and security. In addition, we talked about the challenges, leading directions and applications of SE schemes.