Perhaps you should try some spelling variations:
"harvard world case studies book series." » "harvard world case studies from series.", "harvard world class studies book series.", "harvard worst case studies book series."
"harvard world bank studies food surveys." » "harvard world urban studies food surveys.", "harvard world bank study food surveys.", "harvard world bank studies from surveys.", "harvard world bank studies led surveys.", "harvard world bank studies force surveys.", "harvard world bank studies field surveys."

You may be able to get more results by adjusting your search query.

• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"harvard world case studies book series.\") OR (\"harvard world bank studies food surveys.\"))~".
• Removing quotes may allow a broader search: (( harvard world case studies book series. ) OR ( harvard world bank studies food surveys. ))~.
• Adding a wildcard symbol may retrieve word variants: (("harvard world case studies book series.") OR ("harvard world bank studies food surveys."))*.