Perhaps you should try some spelling variations:
"state factors" » "states factors", "state actors", "state factor"
"state actions" » "state action", "state reactions", "state actors"
"state actor" » "state actors", "state action", "state sector"

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 vector"))) OR ((("state factors") OR ("state actions")))).
• Removing quotes may allow a broader search: (((( state actor ) or ( state vector ))) or ((( state factors ) or ( state actions )))).
• Adding a wildcard symbol may retrieve word variants: (((("state actor") or ("state vector"))) or ((("state factors") or ("state actions"))))*.