An information search system that enables efficient collection of information and support of formation of groups which people who share a same interest can join over a network. This system includes an intermediate server and a central server, wherein the intermediate server retains indexes for searching the content database on the central server. Users issue a search request to the intermediate server and search results are returned and recorded on the intermediate server as a search history. The search history is shared by users and used as references from which retrievable content can be selected.