Perhaps you should try some spelling variations:
"estate sectors" » "estate sector", "estate sektors", "state sector"
"state vectors" » "state vector", "state detectors"
"state action" » "state reactions"
"state actors" » "state factors"

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 action") OR ("state actors"))) OR ((("estate sectors") OR ("state vectors")))).
• Removing quotes may allow a broader search: (((( state action ) or ( state actors ))) or ((( estate sectors ) or ( state vectors )))).
• Adding a wildcard symbol may retrieve word variants: (((("state action") or ("state actors"))) or ((("estate sectors") or ("state vectors"))))*.