Perhaps you should try some spelling variations:
"improving company performance contract." » "improving company performance contracts.", "improving country performance contract.", "improve company performance contract.", "improving compliance performance contract.", "improving community performance contract."
"improving thermal performance evidence." » "improving external performance evidence.", "improving animal performance evidence.", "improving erm performance evidence."

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

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