The Internet Search Service (ISS) was proposed to support an uniform interface for searching on the World Wide Web. Based on this service, a multi-search engine named Octopus had been built. In order to provide more services, such as personal functionality, we provide personalized search for users. In this paper, the policies of personalized search are described. In addition, in order to keep the advantages of the ISS, a personal information-filtering agent is added into the Octopus instead of modifying the architecture or interface of ISS. The feedback mechanism is in cooperation with the filtering mechanism to achieve the functionality of personalized search in a search engine.