Perhaps you should try some spelling variations:
"harvard world case studies book series." » "harvard cold case studies book series.", "harvard world class studies book series.", "harvard world case studies books series.", "harvard world case studies ebook series."
"harvard world bank studies book series." » "harvard cold bank studies book series.", "harvard world urban studies book series.", "harvard world bank study book series.", "harvard world bank studies books series.", "harvard world bank studies ebook series."

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