Perhaps you should try some spelling variations:
"improving bank performance review." » "improving bank performance risk.", "improving bank performance evidence.", "improving urban performance review.", "improving basic performance review.", "improving brain performance review."
"improving animal performance series." » "improving annual performance series.", "improving thermal performance series.", "improving fiscal performance series.", "improving animal performance studies.", "improving animal performance size.", "improving initial performance series.", "improving optimal performance series.", "improving criminal 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 bank performance review.") or ("improving animal performance series."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("improving bank performance review.") OR ("improving animal performance series.")).
• Removing quotes may allow a broader search: (( improving bank performance review. ) or ( improving animal performance series. )).
• Adding a wildcard symbol may retrieve word variants: (("improving bank performance review.") or ("improving animal performance series."))*.