Perhaps you should try some spelling variations:
observational context » observational concepts, observational contacts, observation content
observational cinema » observational clinical, observational economy, observational clues
observational cohort » observational support, observational errors, observational methods

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: ((((observational cinema) OR (observational cohort))) OR (observational context)).
• Adding a wildcard symbol may retrieve word variants: ((((observational cinema) or (observational cohort))) or (observational context))*.