Consider this setup in my Gmail inbox where I have 3 lists:mailing-lists/first-listmailing-lists/second-listmailing-lists/third-listIf I want to search for all unread messages in any sub-label of mailing-lists, is there a better way to search than is:unread label:mailing-list/first-list OR label:mailing-list/second-list OR label:mailing-list/third-listWhat I'm looking for is something more like:is:unread label:mailing-list/* 
Searching within Gmail's nested labels
gmail;search;gmail labels