Perhaps you should try some spelling variations:
"world devices technical paper" » "world services technical paper", "world policies technical paper", "world devices medical paper", "world device technical paper", "hold devices technical paper"
"world banks technical papers" » "world tasks technical papers", "world basics technical papers", "world blocks technical papers", "world bank's technical papers", "world bank technical papers", "world back technical papers"
"work banks technical papers" » "work tasks technical papers", "work basics technical papers", "work blocks technical papers", "work bank technical papers", "work blacks technical papers", "work back technical papers"
"world apis technical papers" » "world api technical papers", "world apps technical papers", "world basics technical papers", "world anis technical papers", "world kpis technical 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 devices technical paper") OR ((((("world banks technical papers") OR ("work banks technical papers"))) OR ("world apis technical papers")))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"world devices technical paper\") or (((((\"world banks technical papers\") OR (\"work banks technical papers\"))) or (\"world apis technical papers\"))))".
• Removing quotes may allow a broader search: (( world devices technical paper ) or ((((( world banks technical papers ) OR ( work banks technical papers ))) or ( world apis technical papers )))).
• Adding a wildcard symbol may retrieve word variants: (("world devices technical paper") or ((((("world banks technical papers") OR ("work banks technical papers"))) or ("world apis technical papers"))))*.