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 country performance measures." » "improving voluntary performance measures.", "importing country performance measures.", "improving community performance measures."

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

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