Perhaps you should try some spelling variations:
"improving food performance series." » "improving food performance metrics.", "improving food performance reviews.", "improving food performance review.", "improving good performance series.", "improving poor performance series.", "improving fund performance series.", "improving land performance series."
"improving bank performance _." » "improving market performance _.", "improving _ performance _.", "improving firm performance _.", "improving land performance _.", "improving urban performance _.", "improving basic performance _."

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

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