The system comprises an interface for acquiring an initial request in natural language, which request is sent to a server of a main database, a storage memory for storing information searching methods, specialized modules for implementing searching methods, a module for responding to the initial request to produce metarequests, said module comprising a unit for extracting the most meaningful words or expressions from the initial request, a search engine for accessing an additional database, a unit for processing the metarequests in order to adapt them to the search engine, a unit for sending the processed metarequests to the search engine giving access to the additional database in order to obtain additional documents corresponding to the initial request, and a unit for transmitting additional documents to the specialized module for processing and formatting which then transmits processed and formatted information to the server in order to enrich the main database.