KQL query for two content types?

I want to create result source that would give results for only two content types from particular site. So, lets say at our site we have couple of different content types content types - A , B, C, D. Whats the keyword query language ( K Q L query) that I need to write so I can see in my result page only items that are containing content types A and B. I was going with : {{searchterms} path:http://intranet ContentType:A and ContentType:B} but its not working, I'm not getting the wanted results.

Thanks,