Enable filtering of dual licensed files

It is a typical task within a compliance review to identify specific licenses (e.g. GPL-2.0-or-later). There are projects (e.g. Qt) with many files under dual licensing scheme (LGPL-3.0 and GPL-2.0-or-later). For easy tracking it would be helpful to filter those files which are not dual licensed and vice versa.

Enabeling typical search strings from search engines could be a solution (e.g. excluding licenses by adding "-" to the search)