Perhaps you should try some spelling variations:
"improving thermal performance targets." » "improving external performance targets.", "improving animal performance targets.", "improving erm performance targets."
"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 targets.") OR ("improving thermal performance evidence."))~.
• Removing quotes may allow a broader search: (( improving thermal performance targets. ) or ( improving thermal performance evidence. ))~.
• Adding a wildcard symbol may retrieve word variants: (("improving thermal performance targets.") or ("improving thermal performance evidence."))*.