Perhaps you should try some spelling variations:
"improving local performance review." » "improving local performance risk.", "improving local performance evidence.", "improving social performance review.", "improving global performance review.", "improving total performance review.", "improving fiscal performance review."
"improving blood performance series." » "improving blood performance studies.", "improving blood performance size.", "improving good performance series.", "improving bond performance series.", "improving floor performance series.", "improving food performance series.", "improving global performance series.", "improving indoor performance series."

Try widening your search to All Fields.

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 review.") or ("improving blood performance series."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("improving local performance review.") OR ("improving blood performance series.")).
• Removing quotes may allow a broader search: (( improving local performance review. ) or ( improving blood performance series. )).
• Adding a wildcard symbol may retrieve word variants: (("improving local performance review.") or ("improving blood performance series."))*.