Perhaps you should try some spelling variations:
"harvard second urban studies from surveys." » "harvard second loan studies from surveys.", "harvard second rural studies from surveys.", "harvard second urban studies from survey.", "harvard second urban studies firm surveys.", "harvard second urban studies force surveys."
"harvard world bank study from series." » "harvard world bank study from sources.", "harvard world bank study from service.", "harvard world bank study from serbian."

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: (("harvard world bank study from series.") OR ("harvard second urban studies from surveys."))~.
• Removing quotes may allow a broader search: (( harvard world bank study from series. ) or ( harvard second urban studies from surveys. ))~.
• Adding a wildcard symbol may retrieve word variants: (("harvard world bank study from series.") or ("harvard second urban studies from surveys."))*.