Perhaps you should try some spelling variations:
"improving country performance series." » "improving country performance studies.", "improving country performance size.", "improving voluntary performance series.", "importing country performance series.", "improving community performance series."
"improving loan performance review." » "improving loan performance risk.", "improving loan performance evidence.", "improving local performance review.", "improving land performance review.", "improving lead 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 country performance series.") or ("improving loan performance review."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("improving country performance series.") OR ("improving loan performance review.")).
• Removing quotes may allow a broader search: (( improving country performance series. ) or ( improving loan performance review. )).
• Adding a wildcard symbol may retrieve word variants: (("improving country performance series.") or ("improving loan performance review."))*.