Perhaps you should try some spelling variations:
"harvard world war studies book series." » "harvard cold war studies book series.", "harvard world war stories book series.", "harvard world early studies book series.", "harvard world war studies books series.", "harvard world war studies ebook series."
"harvard world case studies from surveys." » "harvard cold case studies from surveys.", "harvard world case studies from survey.", "harvard world case studies firm surveys.", "harvard world case studies force surveys.", "harvard world class studies from surveys."

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