Perhaps you should try some spelling variations:
"improving rural performance series." » "improving rural performance metrics.", "improving rural performance reviews.", "improving rural performance review.", "improving pupil performance series.", "improving thermal performance series.", "improving overall performance series.", "improving urban performance series.", "improving social performance series."
"improving country performance evidence." » "improving voluntary performance evidence.", "importing country performance evidence.", "borrowing country performance evidence."

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 country performance evidence."))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"improving rural performance series.\") OR (\"improving country performance evidence.\"))".
• Removing quotes may allow a broader search: (( improving rural performance series. ) OR ( improving country performance evidence. )).
• Adding a wildcard symbol may retrieve word variants: (("improving rural performance series.") OR ("improving country performance evidence."))*.