You are comparing to Nominatim. Even a particular instance of Nominatim (the operator can feed other data sources into the index).

I don't think it does much of any contextualization. It might recognize 'forest' as a specific type of feature, but I believe it would only use that to prioritize results, not exclude them (but I haven't taken the time to figure out how to check this).

Photon is another search system that uses OSM data:

http://wiki.openstreetmap.org/wiki/Photon

I guess Komoot uses it:

https://www.komoot.de/plan

It succeeds with "Sambisa Forest".