Perhaps you should try some spelling variations:
"improving indoor performance series." » "improving outdoor performance series.", "improving poor performance series.", "improving donor performance series.", "improving indoor performance studies.", "improving indoor performance size.", "improving india's performance series.", "improving food performance series.", "improving gender performance series."
"improving country performance risk." » "improving voluntary performance risk.", "importing country performance risk.", "improving community performance risk.", "improving country performance 2019."

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("improving country performance risk.") or ("improving indoor performance series."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("improving country performance risk.") OR ("improving indoor performance series.")).
• Removing quotes may allow a broader search: (( improving country performance risk. ) or ( improving indoor performance series. )).
• Adding a wildcard symbol may retrieve word variants: (("improving country performance risk.") or ("improving indoor performance series."))*.