Perhaps you should try some spelling variations:
"word based working papers" » "word base working papers", "word based parking papers", "word basic working papers", "work based working papers", "card based working papers", "keyword based working papers"
"world world working paper" » "world works working paper", "world work working paper", "world world making paper", "old world working paper"

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: (("word based working papers") OR ("world world working paper")).
• Removing quotes may allow a broader search: (( word based working papers ) or ( world world working paper )).
• Adding a wildcard symbol may retrieve word variants: (("word based working papers") or ("world world working paper"))*.