Perhaps you should try some spelling variations:
"world brand working paper" » "world band working paper", "world branch working paper", "world board working paper", "word brand working paper", "world bank working paper", "world brand working papers"
"world bond working paper" » "world bonds working paper", "world band working paper", "world bold working paper", "world beyond working paper", "world board working paper", "world blind working paper", "world bond working papers"

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