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 farmers performance series." » "improving firms performance series.", "improving markets performance series.", "improving workers performance series.", "improving farmers performance studies.", "improving farmers performance size.", "improving access performance series.", "improving care performance series."

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 farmers performance series."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("improving rural performance contract.") OR ("improving farmers performance series."))*.
• Removing quotes may allow a broader search: (( improving rural performance contract. ) or ( improving farmers performance series. ))*.