Suppose the user wants to learn a particular concept related to a particular domain. Then the user will be linked to the most optimal cluster i.e. the cluster which has the highest membership for that particular con- cept and thus the search for documents related to that concept would be limited to the documents belonging to the optimal cluster rather the entire pool of documents. This ensures an efficient searching of document related to a particular concept. The process of document retrieval is discussed in the following section.