Perhaps you should try some spelling variations:
world economies » world economics, world economic, world economy
boarding papers » boarding pass, boarding passes, learning papers
working papers » working paper
kcd economics » oecd economies, land economics, food economics

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: ((world economies) OR (kcd economics)) department ((boarding papers) OR (working papers)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((world economies) or (kcd economics)) department ((boarding papers) OR (working papers))".
• Adding a wildcard symbol may retrieve word variants: ((world economies) or (kcd economics)) department ((boarding papers) OR (working papers))*.