exclude term in YouTube Data API without including term -

i'm using youtube data api's search.list method return list of videos date. i'm interested in filtering out content without having specify search term. documentation specifies can use - operator boolean not, seems work if precede search term, meaning can this:

q:'food -pizza' 

which return results query term 'food' not 'pizza'. want return any result excluding pizza you'd think work:

q:'-pizza' 

but returns empty array (no results). doing wrong? there way exclude terms without having specify specific search term include before hand?