Perhaps you should try some spelling variations:
"central asia research _ series." » "central basic research _ series.", "central cgiar research _ series.", "central a research _ series."
"central de research food survey." » "central de research tool survey.", "central de research fund survey.", "central de research focus survey.", "central does research food survey.", "central key research food survey.", "central led research food survey.", "central de research from survey.", "central de research hold survey.", "central de research force survey.", "centrale des research food survey.", "central _ research food survey.", "centro de research food survey."

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 food survey."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("central asia research _ series.") OR ("central de research food survey."))*.
• Removing quotes may allow a broader search: (( central asia research _ series. ) or ( central de research food survey. ))*.