For example, we input the following five items: grid, information retrieval, semantic, performance, evaluation. The semantic expansion technology and concept similarity calculation method are used. The retrieval recall factor is as table 1. A relatively good retrieval recall factor can be obtained by selecting 0.5 as the threshold to determine the similarity of two concepts. The retrieval recall factor based on domain ontology is higher than that based on keyword, and the better retrieval result can be achieved. If the similarity parameter is set to 0.6 or higher, the pertinency factor of the search can be improved, the result is as table 2.