As a large fraction of available information resides in databases, the need for facilitating access for the large majority of users becomes increasingly more important. Precis queries are free-form queries that generate entire multi-relation databases, which are logical subsets of existing ones. A logical subset contains not only items directly related to the given query selections but also items implicitly related to them in various ways with the purpose of providing to the user much greater insight into the original data. This paper is concerned with the definition and generation of logical database subsets based on precis queries under a generalized perspective that removes several restrictions of previous work and handles queries containing multiple terms combined using the operators AND, OR, and NOT.