Perhaps you should try some spelling variations:
"central a research program success." » "central a research programs success.", "central a research project success.", "central a research program stress.", "central 2 research program success.", "central la research program success.", "central _ research program success.", "central 1 research program success."
"central tax research program synthesis." » "central tax research programs synthesis.", "central tax research project synthesis.", "central 2 research program synthesis.", "central 2.1 research program synthesis.", "central 2.2 research program synthesis.", "central taxes research program synthesis.", "central bank research program synthesis."

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("central a research program success.") or ("central tax research program synthesis."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("central a research program success.") OR ("central tax research program synthesis."))*.
• Removing quotes may allow a broader search: (( central a research program success. ) or ( central tax research program synthesis. ))*.