Man pages matching name mongoc_read_concern_get_level in section 3:

mongoc_read_concern_get_level.3.en	debian 10 / libmongoc-doc
mongoc_read_concern_get_level.3.en	debian 11 / libmongoc-doc
mongoc_read_concern_get_level.3.en	debian 12 / libmongoc-doc