WordNet sense 1 (an operation that determines whether one or more of a set of items has a specified property):

lookup

WordNet sense 2 (search or seek):

look

WordNet sense 3 (try to locate or discover, or try to establish the existence of):

seek, look for

WordNet sense 4 (the activity of looking thoroughly in order to find something or someone):

hunt, hunting

WordNet sense 5 (inquire into):

explore, research