Perhaps you should try some spelling variations:
"improving rural performance contract." » "improving rural performance contracts.", "improving euract performance contract.", "improving larval performance contract.", "improving pupil performance contract."
"improving firm performances series." » "improving firm performance series.", "improving firm performance merits.", "improving firm performance studies.", "improving firms performance series.", "improving from performance series.", "improving firms performances series.", "improving air performances series.", "improving erm performances 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 rural performance contract.") or ("improving firm performances series."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("improving rural performance contract.") OR ("improving firm performances series.")).
• Removing quotes may allow a broader search: (( improving rural performance contract. ) or ( improving firm performances series. )).
• Adding a wildcard symbol may retrieve word variants: (("improving rural performance contract.") or ("improving firm performances series."))*.