Perhaps you should try some spelling variations:
"state sector" » "estate sector", "state vectors", "state section"
"state actor" » "state action", "state after", "state acts"
"state actors" » "state actions", "state afters", "state actss", "state factors"
"state actss" » "state acts", "state access", "state across"

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: (((((("state actor") OR ("state actors"))) OR ((("state sector") OR ((("state vector") OR ("space vector"))))))) OR ("state actss")).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((((\"state actor\") OR (\"state actors\"))) or (((\"state sector\") or (((\"state vector\") or (\"space vector\"))))))) or (\"state actss\"))".
• Removing quotes may allow a broader search: (((((( state actor ) OR ( state actors ))) or ((( state sector ) or ((( state vector ) or ( space vector ))))))) or ( state actss )).
• Adding a wildcard symbol may retrieve word variants: (((((("state actor") OR ("state actors"))) or ((("state sector") or ((("state vector") or ("space vector"))))))) or ("state actss"))*.