Perhaps you should try some spelling variations:
"improving company performance evidence." » "improving country performance evidence.", "improve company performance evidence.", "improving compliance performance evidence.", "improving community performance evidence."
"improving social performance series." » "improving school performance series.", "improving fiscal performance series.", "improving financial performance series.", "improving social performance studies.", "improving social performance size."

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("improving social performance series.") or ("improving company performance evidence."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("improving social performance series.") OR ("improving company performance evidence."))*.
• Removing quotes may allow a broader search: (( improving social performance series. ) or ( improving company performance evidence. ))*.