Perhaps you should try some spelling variations:
"improving firms performance risk." » "improving firm performance risk.", "improving firm performances risk.", "improving funds performance risk.", "improving firms performance 2019.", "improving farmers performance risk.", "importing firms performance risk.", "improving air performance risk."
"improving based performance evidence." » "improving board performance evidence.", "improving fund performance evidence.", "improving good performance evidence.", "improving basic performance evidence.", "improving care performance evidence.", "improving asset 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 firms performance risk.") or ("improving based performance evidence."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("improving firms performance risk.") OR ("improving based performance evidence."))*.
• Removing quotes may allow a broader search: (( improving firms performance risk. ) or ( improving based performance evidence. ))*.