Users and uses of internet is growing tremendously these days which causing an extreme trouble and efforts at user side to get web pages searched which are as per concern and relevant to user's requirement Generally users approach to search web pages from a large available hierarchy of concepts or use a query to browse web pages from available search engine and receive results based on search pattern where few of the results are relevant to search and most of them are not. Web crawler plays an important role in search engine and act as a key element when performance is considered. This paper includes domain engineering concept and keyword driven crawling with relevancy decision mechanism and uses Ontology concepts which ensures the best path for improving crawler's performance. This paper introduces extraction of URLs based on keyword or search criteria. It extracts URLs for web pages which contains searched keyword in their content and considers such pages only as important and doesn't download web pages irrelevant to search. It offers high optimality comparing with traditional web crawler and can enhance search efficiency with more accuracy.