15. The method according to claim 13 , wherein the determining the final domain comprise determining a user's intention from at least one of the extracted first and second utterance elements and the detected candidate domain to determine whether or not a context initialization occurred, and in response to determining that the context initialization has not occurred, determining at least one candidate domain from among the detected candidate domains as the final domain based on a previous domain, the previous domain being a domain determined from a user's previous utterance voice before receiving the text of the user's utterance voice signal.
13. The method according to claim 11 , wherein the detecting the expansion domain comprises: using a multi classifier to detect a subordinate candidate domain related to the detected expansion domain, where the main action corresponding to the first utterance element and the component slot corresponding to the extracted second utterance element are matched to each other is detected, and when the expansion domain is not detected, the detecting the expansion domain incorporates using a multi-classifier to detect a candidate domain, where the main action corresponding to the first utterance element and the component slot corresponding to the second utterance element are matched to each other.