Perhaps you should try some spelling variations:
"central action research firm series." » "central national research firm series.", "central section research firm series.", "central nation research firm series.", "centric action research firm series.", "central action research from series.", "central action research field series.", "central action research final series.", "central action research film series.", "central action research forum series."
"central cgiar research a series." » "central asia research a series.", "central asian research a series.", "central city research a series."

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: (("central action research firm series.") or ("central cgiar research a series."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("central action research firm series.") OR ("central cgiar research a series.")).
• Removing quotes may allow a broader search: (( central action research firm series. ) or ( central cgiar research a series. )).
• Adding a wildcard symbol may retrieve word variants: (("central action research firm series.") or ("central cgiar research a series."))*.