One of the biggest difficulties faced by researchers is how to retrieve relevant information and how to filter it. In this way, it is good to emphasize that theinformation expert can be considered the first filter of the system. The use of documentary language instruments is necessary and gives a substantial contribution for the success of the service offered. This paper defends the necessity of an information professional to contribute in the coordination of information retrieval systems and also focus on the use of thesaurus, in databases, both as tools of work of the indexes and as a powerful tool to help the process of information retrieval.
librarians; information professional; thesaurus; information retrieval; documentary language; databases; information filters