Query_string exact match returning word derivations


I am using elasticsearch query_string to attempt to return exact match results when using quotes. It is returning derivations of the root words I am searching for, not the exact match.

For example, if I search for:

"web developer"

The search results also return:

web developer
web development

phrase_slop is set to 0.

When the index is built content is passed through a stop filter and stemmer.