Perhaps you should try some spelling variations:
"improving local performance series." » "improving local performance studies.", "improving local performance size.", "improving social performance series.", "improving global performance series.", "improving total performance series.", "improving fiscal performance series."
"improving eco performance series." » "improving eco performance studies.", "improving eco performance size.", "improving do performance series.", "improving ceo performance series.", "improving core performance series.", "improving co performance series.", "improving e performance series.", "improving eap performance series."

Try widening your search to All Fields.

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

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