Perhaps you should try some spelling variations:
"improving voluntary performance review." » "improving country performance review.", "improving entry performance review.", "improving budgetary performance review.", "improving voluntary performance risk.", "improving voluntary performance evidence."
"improving local performance series." » "improving local performance metrics.", "improving local performance reviews.", "improving local performance targets.", "improving social performance series.", "improving loan performance series.", "improving fiscal performance series.", "improving global performance series."

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("improving local performance series.") or ("improving voluntary performance review."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("improving local performance series.") OR ("improving voluntary performance review."))*.
• Removing quotes may allow a broader search: (( improving local performance series. ) or ( improving voluntary performance review. ))*.