Searching for a specific word

I feel like I must be missing something basic, but I've looked through all the search functions I could find, but nothing seemed to address my question. 

How do I search for "faithful" and not "faith"?

When I type faithful into the search box it comes back with all the uses of faith, faithful, faithfulness, etc. I tried using quotation marks to search "faithful", but still it comes back with both results. 

I tried changing the search from Bible to Basic to Morph, but that doesn't change anything. 

Anyone know how to do this? I guess theoretically, a workaround would be to search for πιστός only when it appears as an adjective, but it seems like searching for a specific word shouldn't be so difficult. 

Thanks, 

Tim