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 court performance evidence." » "improving country performance evidence.", "improving export performance evidence.", "improving our performance evidence.", "improving your performance evidence.", "improving care performance evidence."

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