Perhaps you should try some spelling variations:
"improving local performance reviews." » "improving local performance review.", "improving local performance reports.", "improving local performance risks.", "improving social performance reviews.", "improving global performance reviews.", "improving total performance reviews.", "improving fiscal performance reviews."
"improving human performance series." » "improving human performance studies.", "improving human performance size.", "improving loan performance series.", "improving thermal performance series.", "improving chain 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 human performance series.") or ("improving local performance reviews."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("improving human performance series.") OR ("improving local performance reviews.")).
• Removing quotes may allow a broader search: (( improving human performance series. ) or ( improving local performance reviews. )).
• Adding a wildcard symbol may retrieve word variants: (("improving human performance series.") or ("improving local performance reviews."))*.