A method and a modification system for modifying a search query for a user are provided. The method includes receiving at least one search query from a user; determining a present context of the user, based on the at least one search query and on-device data; identifying at least one relevant attribute related to the search query based on the present context of the user and a personalized knowledge graph, wherein the personalized knowledge graph is dynamically generated based on the on-device data; and modifying the search query, based on the at least one relevant attribute and a relation of the at least one relevant attribute with the search query, to obtain at least one modified search query.