LDAP based search mechanisms in Grid environment are syntactic based and do not support semantic information extraction. With the quick development of Semantic Grid, it demands a more flexible and powerful search mechanism for Grid information discovery. We propose a new search mechanism which extends LDAP and can be used in the Semantic Grid environment for semantic searching of relevant information. The mechanism uses an ontology learning model which maps WordNet lexicon into OWL ontologies. Such ontology assistant mechanism can utilize the reasoning services from particular description logic systems and make use of more machine automation in the searching process.