An approach is provided for efficiently searching information in an information space utilizing information signatures. A signature application receives queries over information sources. The signature application, for each of the queries, generates a polynomial by defining the each query against the information sources as input parameters in polynomial form. The signature application provides irreducible polynomials over a finite field of a degree of orthogonality by factoring polynomials generated from the queries. The signature application adjusts the degree of orthogonality of the irreducible polynomials to provide adjusted irreducible polynomials, each of which is a signature and corresponds to a signature fragment, such that the signature fragments have overlapping portions. The signature application causes at least in part storage of the signatures or the signature fragments in a signature domain over an information space.