Perhaps you should try some spelling variations:
"world macro working paper" » "world macros working paper", "world mac working paper", "world avro working paper", "word macro working paper", "world mark working paper"
"world map working paper" » "world maps working paper", "world gap working paper", "world up working paper"
"world map working papers" » "world maps working papers", "world gap working papers", "world up working papers"

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: (((("world map working paper") OR ("world map working papers"))) OR ("world macro working paper")).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"world map working paper\") OR (\"world map working papers\"))) or (\"world macro working paper\"))".
• Removing quotes may allow a broader search: (((( world map working paper ) OR ( world map working papers ))) or ( world macro working paper )).
• Adding a wildcard symbol may retrieve word variants: (((("world map working paper") OR ("world map working papers"))) or ("world macro working paper"))*.