The repoquery plugin does not behave like the old yum repoquery tool unless you use --alldeps. This isn't obvious from either of the yum2dnf(8) or dnf.plugin.repoquery(8) man pages.
The dnf.plugin.repoquery(8) man page should show the use of --alldeps in the examples, otherwise people get confused why dnf repoquery gives no results for an equivalent /usr/bin/repoquery search.
The documentation of --alldeps is also not very clear what it does, so you have a poorly documented option that is essential for getting the traditional behaviour people are used to, but which isn't shown in any examples.
The problem is fixed by pull-request: https://github.com/rpm-software-management/dnf/pull/505
*** Bug 1347105 has been marked as a duplicate of this bug. ***
This package has changed ownership in the Fedora Package Database. Reassigning to the new owner of this component.
Fixed as part of DNF 2.0 which will be availabla at some point soon.