11. A method that utilizes a processor to provide a search result, the method comprising: receiving a search term from a user; extracting, via the processor, information corresponding to at least one of a first personal network associated with the search term and a second personal network different than the first personal network; extracting information corresponding to at least one neighbor having interests corresponding to interests of the user based, at least in part, on a profile of the user; and providing a document associated with at least one of the first personal network and the second personal network as a search result of the search term, wherein extracting the information corresponding to the at least one neighbor comprises: providing the profile of the user using keywords provided in a document prepared by the user, the keywords being time-variable and corresponding to keywords having the highest frequency of occurrence in the document.
11. A method that utilizes a processor to provide a search result, the method comprising: receiving a search term from a user; extracting, via the processor, information corresponding to at least one of a first personal network associated with the search term and a second personal network different than the first personal network; extracting information corresponding to at least one neighbor having interests corresponding to interests of the user based, at least in part, on a profile of the user; and providing a document associated with at least one of the first personal network and the second personal network as a search result of the search term, wherein extracting the information corresponding to the at least one neighbor comprises: providing the profile of the user using keywords provided in a document prepared by the user, the keywords being time-variable and corresponding to keywords having the highest frequency of occurrence in the document. 12. The method of claim 11 , further comprising: setting at least one of communities joined by the user, the at least one neighbor, and communities joined by the at least one neighbor, to be a personal network of the user.