Perhaps you should try some spelling variations:
"improving sme performance review." » "improving sme performance evidence.", "improving time performance review.", "improving use performance review.", "improving state performance review.", "improving _ performance review.", "improving air performance review.", "improving tax performance review."
"improving firm performance risk." » "improving _ performance risk.", "improving firm performance size.", "improving firm performance based.", "improving firm performance _.", "improving firms performance risk.", "improving air performance risk.", "improving birth performance risk."

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("improving firm performance risk.") OR ("improving sme performance review."))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"improving firm performance risk.\") OR (\"improving sme performance review.\"))".
• Removing quotes may allow a broader search: (( improving firm performance risk. ) OR ( improving sme performance review. )).
• Adding a wildcard symbol may retrieve word variants: (("improving firm performance risk.") OR ("improving sme performance review."))*.