Perhaps you should try some spelling variations:
"world back technical paper" » "world back technical papers", "world bank technical paper", "world pack technical paper", "world rack technical paper", "world black technical paper", "world jack technical paper"
"world bands technical paper" » "world bands technical papers", "world pandas technical paper", "world bank technical paper", "world bars technical paper", "world hands technical paper", "world bank's technical paper", "world bandar technical paper"
"world banks technical paper" » "world banks technical papers", "world tasks technical paper", "world basics technical paper", "world blocks technical paper", "world bank's technical paper", "world bank technical paper", "work banks technical 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: (("world back technical paper") OR ((("world bands technical paper") OR ("world banks technical paper")))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"world back technical paper\") or (((\"world bands technical paper\") OR (\"world banks technical paper\"))))".
• Removing quotes may allow a broader search: (( world back technical paper ) or ((( world bands technical paper ) OR ( world banks technical paper )))).
• Adding a wildcard symbol may retrieve word variants: (("world back technical paper") or ((("world bands technical paper") OR ("world banks technical paper"))))*.