Perhaps you should try some spelling variations:
"improving thermal performance based." » "improving external performance based.", "improving animal performance based.", "improving erm performance based."
"improving basic performance evidence." » "improving based performance evidence.", "improving music performance evidence.", "improving baseline performance evidence.", "improving air performance evidence.", "improve basic performance evidence."

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

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