Abstract: Open source software projects have become a kind of important sources in software reuse．When the source code and code related documents in a project are very large,it is time-consuming for end-users to find the right information (code or document) segments.We proposed a natural language based software information retrieval approach,which helps developers to get the software information they need more quickly and conveniently.Based on this approach,we designed and implemented a natural language based software information search engine (NaLSiSe)．We took Lucene as an example to illustrate how NaLSiSe automatically analyses and organizes the related software information,constructs query in natural language based search engine so as to improve the precision.

Key words: Software reuse,Software project,Information retrieval,Natural language question