Perhaps you should try some spelling variations:
regarding papers » regarding expert, regarding others, regarding power
based economics » based economic, based economy, based proteomics
oecd economies » oecd economic
regarding aps » regarding cps, regarding a, regarding aa

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: ((based economics) OR (oecd economies)) development ((regarding papers) OR (regarding aps)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((based economics) or (oecd economies)) development ((regarding papers) OR (regarding aps))".
• Adding a wildcard symbol may retrieve word variants: ((based economics) or (oecd economies)) development ((regarding papers) OR (regarding aps))*.