Perhaps you should try some spelling variations:
"improving thermal performance evidence." » "improving maternal performance evidence.", "improving rural performance evidence.", "improving mental performance evidence."
"improving human performance measures." » "improving loan performance measures.", "improving company performance measures.", "improving animal performance measures.", "improving urban performance measures.", "improving rural performance measures."

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