Perhaps you should try some spelling variations:
observational clinical » observation clinical, observations clinical, observational logic
observational concepts » observation concepts, observational concerns, observational conceptual
observational economy » observational astronomy, observational cohort, observational errors
observational cinema » observational context, observational clues, observational case

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 clinical))) OR (observational economy))) OR (observational concepts)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((((observational cinema) OR (observational clinical))) or (observational economy))) or (observational concepts))".
• Adding a wildcard symbol may retrieve word variants: ((((((observational cinema) OR (observational clinical))) or (observational economy))) or (observational concepts))*.