Perhaps you should try some spelling variations:
"central de research project surveys." » "central de research project survey.", "central de research project success.", "central does research project surveys.", "central key research project surveys.", "central led research project surveys.", "centrale des research project surveys.", "central _ research project surveys.", "centro de research project surveys."
"central asia research _ series." » "central basic research _ series.", "central cgiar research _ series.", "central a research _ series."

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("central asia research _ series.") or ("central de research project surveys."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("central asia research _ series.") OR ("central de research project surveys.")).
• Removing quotes may allow a broader search: (( central asia research _ series. ) or ( central de research project surveys. )).
• Adding a wildcard symbol may retrieve word variants: (("central asia research _ series.") or ("central de research project surveys."))*.