1. An apparatus, including at least one processing device, the apparatus comprising: a calculation unit to calculate respective scores between a plurality of audio files and a query; a dynamic clustering unit to identify first audio files, of the plurality of audio files, based on the calculated respective scores between the plurality of audio files and the query, and to dynamically cluster the identified first audio files by calculating scores between the identified first audio files, with dynamic clustering of the identified first audio files being repeated based on relatedness between calculated values representative of each cluster generated in separate dynamic clusterings of the identified first audio files; a static clustering unit to identify second audio files, of the plurality of audio files, based on the calculated respective scores between the plurality of audio files and the query, and to cluster the identified second audio files based on respective weights of core index words of the identified second audio files, wherein the weights of the core index words are respective weights of extracted core index words for the plurality of audio files; a cluster overlap unit to use the at least one processing device to overlap the dynamically clustered first identified audio files with the statically clustered second identified audio files, implemented as through at least one processor, to generate an overlapped cluster having audio files similar to the query; and an output to output to a user a result of the overlapping to generate the overlapped cluster, wherein the relatedness between calculated values representative of each cluster, in the repeating of the dynamic clustering of the identified first audio files based on the relatedness between calculated values representative of each cluster generated in separate dynamic clusterings of the identified first audio files, is based on relatedness between calculated central points of each dynamically generated cluster, wherein if the calculated central point remains unchanged during repeating of the dynamic clustering, the dynamic clustering unit stops the dynamic clustering.