Perhaps you should try some spelling variations:
"improving air performance series." » "improving air performance metrics.", "improving air performance reviews.", "improving air performance review.", "improving firm performance series.", "improving a performance series.", "improving ii performance series.", "improving water performance series.", "improving land performance series.", "improving _ performance series."
"improving public performance evidence." » "improving building performance evidence.", "improving specific performance evidence.", "improving quality 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 air performance series.") or ("improving public performance evidence."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("improving air performance series.") OR ("improving public performance evidence.")).
• Removing quotes may allow a broader search: (( improving air performance series. ) or ( improving public performance evidence. )).
• Adding a wildcard symbol may retrieve word variants: (("improving air performance series.") or ("improving public performance evidence."))*.