Abstract: Cloud computing is a method for delivering information technology (IT) services in which resources are retrieved from the Internet through web-based tools and applications, as opposed to a direct connection to a server. Rather than keeping files on a proprietary hard drive or local storage device, cloud-based storage makes it possible to save them to a remote database. Cloud computing is a forth coming revolution in information technology (IT) industry because of its performance , accessibility, low cost and many other luxuries. It is an approach to maximize the capacity or step up capabilities vigorously without investing in new infrastructure, nurturing new personnel or licensing new software. It provides gigantic storage for data and faster computing to customers over the internet. It essentially shifts the database and application software to the large data centers, i.e., cloud, where management of data and services may not be completely trustworthy. To keep the outsourced data more secure ,the owner of the data will encrypt the data using AES encryption method. And owner provide the service to search and use these outsourced data by other users in the cloud. But it difficult perform the search on the encrypted outsourced data, for these First, I am introduce the relevance scores and preference factors upon keywords which enable the precise keyword search and personalized user experience. Second, I develop a practical and very efficient multi-keyword search scheme. The proposed scheme can support complicated logic search the mixed “AND”, “OR” and “NO” operations of keywords. Third, I further employ the classified sub-dictionaries technique to achieve better efficiency on index building, trapdoor generating and query. Through this I will achieve efficient search .