Abstract: Methods and systems are provided to present the search results in response to a search query that is submitted to a document retrieval system, such as a search engine. The search results are presented with a second-retrieval model that constructs multiple derived queries for the search query with a first small-document retrieval process, and then generates and outputs the results based on the retrieval of search results of at least part of the derived queries. One embodiment of the invention provides a method for grouping the search results, which presents ranked derived queries together with their search results to the user, in such a way that derived queries with higher ranks and top-ranked documents of each derived query are preferentially presented, and the grouped results are displayed and navigated in independent framed subareas of an output window.

Abstract: Methods and systems are presented to predetermine and record the classes of each indexed document with respect to each of its index keywords, and to provide high quality and relevant classification of the document when it is searched with said keyword. Document classes, recorded in advance, are used as the clustering information of each document in the search results to realize efficient, large-scale and high quality search result clustering. One embodiment provides a method for search result clustering, which includes recording the classes of each indexed document when the document is searched with each of its index keywords. This method further includes grouping the search results according to the classes of each result document with respect to the keyword or keywords contained in the search query.