12. The method of claim 10 , wherein said distributing one of plural preset domain specialized question and answer engines distributes a domain with respect to the user's question based on a law dictionary previously established for each domain or a learning model established through analyzing the language of learning data and through mechanical learning of learning quality.
13. The method of claim 12 , wherein said distributing one of plural preset domain specialized question and answer engines includes: analyzing the language of the user's question; identifying and distributing a domain for the user's question based on the law dictionary though the language analysis result; and distributing a domain with respect to the user's question based on the learning model when a domain is not distributed based on the law dictionary.