Perhaps you should try some spelling variations:
"central tax research force survey." » "central tax research focus survey.", "central tax research firm survey.", "central tax research food survey.", "central a research force survey.", "central bank research force survey.", "central _ research force survey.", "central taxes research force survey."
"central basic research team series." » "central bank research team series.", "central asia research team series.", "central banks research team series.", "central basic research areas series.", "central basic research a 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 basic research team series.") or ("central tax research force survey."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("central basic research team series.") OR ("central tax research force survey.")).
• Removing quotes may allow a broader search: (( central basic research team series. ) or ( central tax research force survey. )).
• Adding a wildcard symbol may retrieve word variants: (("central basic research team series.") or ("central tax research force survey."))*.