Perhaps you should try some spelling variations:
"improving rural performance series." » "improving rural performance studies.", "improving rural performance size.", "improving euract performance series.", "improving larval performance series.", "improving pupil performance series."
"improving bank performance review." » "improving bank performance risk.", "improving bank performance evidence.", "improving urban performance review.", "improving basic performance review.", "improving brain performance review."

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

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