Perhaps you should try some spelling variations:
"improving erm performance series." » "improving erm performance studies.", "improving erm performance size.", "improving esm performance series.", "improving firm performance series.", "improving team performance series.", "improving ers performance series.", "improving e performance series.", "improving eap performance series."
"improving rural performance risk." » "improving euract performance risk.", "improving larval performance risk.", "improving pupil performance risk.", "improving rural 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 erm performance series.") or ("improving rural performance risk."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("improving erm performance series.") OR ("improving rural performance risk.")).
• Removing quotes may allow a broader search: (( improving erm performance series. ) or ( improving rural performance risk. )).
• Adding a wildcard symbol may retrieve word variants: (("improving erm performance series.") or ("improving rural performance risk."))*.