Perhaps you should try some spelling variations:
"improving rural performance metrics." » "improving rural performance measures.", "improving euract performance metrics.", "improving larval performance metrics.", "improving pupil performance metrics."
"improve past performance series." » "improve past performance studies.", "improve past performance size.", "improve plant performance series.", "improve port performance series.", "improve transit performance series.", "improve post performance series.", "improve asi performance series.", "improve cost 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: (("improve past performance series.") or ("improving rural performance metrics."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("improve past performance series.") OR ("improving rural performance metrics.")).
• Removing quotes may allow a broader search: (( improve past performance series. ) or ( improving rural performance metrics. )).
• Adding a wildcard symbol may retrieve word variants: (("improve past performance series.") or ("improving rural performance metrics."))*.