Perhaps you should try some spelling variations:
"harvard world early studies book series." » "harvard world earlier studies book series.", "harvard world early stages book series.", "harvard bord early studies book series.", "harvard world earth studies book series.", "harvard world karl studies book series.", "harvard world early studies books series.", "harvard world early studies ebook series."
"harvard cold bank studies food surveys." » "harvard cold urban studies food surveys.", "harvard cold bank study food surveys.", "harvard cold bank studies from surveys.", "harvard cold bank students food surveys.", "harvard cold bank studies field surveys.", "harvard cold bank studies force surveys.", "harvard world bank studies food surveys.", "harvard bond bank studies food surveys.", "harvard good bank studies food surveys."

Try widening your search to All Fields.

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("harvard world early studies book series.") or ("harvard cold bank studies food surveys."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("harvard world early studies book series.") OR ("harvard cold bank studies food surveys.")).
• Removing quotes may allow a broader search: (( harvard world early studies book series. ) or ( harvard cold bank studies food surveys. )).
• Adding a wildcard symbol may retrieve word variants: (("harvard world early studies book series.") or ("harvard cold bank studies food surveys."))*.