Perhaps you should try some spelling variations:
security functions » security foundations, security notions, security solutions
security factors » security features, security fast, security feature
security sector » security second, security secure
security actor » security act, security after, security across

Try widening your search to All Fields.

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: %((((security actor) OR (security sector))) OR (((security factors) OR (security functions))))%22.
• The words AND, OR and NOT may confuse the search; try adding quotes: "%((((security actor) or (security sector))) or (((security factors) OR (security functions))))%22".
• Adding a wildcard symbol may retrieve word variants: %((((security actor) or (security sector))) or (((security factors) OR (security functions))))%22*.