Perhaps you should try some spelling variations:
"improving thermal performance contract." » "improving thermal performance contracts.", "improving external performance contract.", "improving animal performance contract.", "improving erm performance contract."
"improving rural performance review." » "improving rural performance risk.", "improving rural performance evidence.", "improving euract performance review.", "improving larval performance review.", "improving pupil performance review."

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 review.") or ("improving thermal performance contract."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("improving rural performance review.") OR ("improving thermal performance contract.")).
• Removing quotes may allow a broader search: (( improving rural performance review. ) or ( improving thermal performance contract. )).
• Adding a wildcard symbol may retrieve word variants: (("improving rural performance review.") or ("improving thermal performance contract."))*.