Outsourcing　data　to　the　cloud　has　become　prevalent,　so　Searchable　Symmetric　Encryption　(SSE),　one　of　the　methods　for　protecting　outsourced　data,　has　arisen　widespread　interest.　Moreover,　many　novel　technologies　and　theories　have　emerged,　especially　for　the　attacks　on　SSE　and　privacy-preserving.　But　most　surveys　related　to　SSE　concentrate　on　one　aspect　(e.g.,　single　keyword　search,　fuzzy　keyword　search)　or　lack　in-depth　analysis.　Therefore,　we　revisit　the　existing　work　and　conduct　a　comprehensive　analysis　and　summary.　We　provide　an　overview　of　state-of-the-art　in　SSE　and　focus　on　the　privacy　it　can　protect.　Generally,　(1)　we　study　the　work　of　the　past　few　decades　and　classify　SSE　based　on　query　expressiveness.　Meanwhile,　we　summarize　the　existing　schemes　and　analyze　their　performance　on　efficiency,　storage　space,　index　structures,　and　so　on.;　(2)　we　complement　the　gap　in　the　privacy　of　SSE　and　introduce　in　detail　the　attacks　and　the　related　defenses;　(3)　we　discuss　the　open　issues　and　challenges　in　existing　schemes　and　future　research　directions.　We　desire　that　our　work　will　help　novices　to　grasp　and　understand　SSE　comprehensively.　We　expect　it　can　inspire　the　SSE　community　to　discover　more　crucial　leakages　and　design　more　efficient　and　secure　constructions.