Research on Efficient Searchable Data Encryption in Cloud Storage focuses on enabling secure and privacy-preserving data retrieval without compromising performance or confidentiality. Modern approaches combine lightweight cryptographic techniques with advanced searchable symmetric and public-key encryption schemes to allow users to search encrypted data using encrypted queries. These methods emphasize minimizing computational overhead, reducing index leakage, and supporting dynamic data operations such as insertion, deletion, and permission management. Hierarchical and identity-based encryption frameworks offer fine-grained access control, while lattice-based and homomorphic encryption approaches enhance security against quantum and adaptive attacks. Recent trends also explore integrating searchable encryption with healthcare and IoT-cloud environments, ensuring both efficiency and resilience against query pattern analysis. The overall goal is to achieve fast, secure, and scalable keyword-based search mechanisms suitable for large-scale encrypted cloud storage systems.