Perhaps you should try some spelling variations:
"improving thermal performance reviews." » "improving thermal performance review.", "improving thermal performance reports.", "improving thermal performance risks.", "improving maternal performance reviews.", "improving rural performance reviews.", "improving human performance reviews."
"improving poor performance measures." » "improving export performance measures.", "improving sector performance measures.", "improving _ performance measures.", "improving power performance measures.", "improving food performance measures.", "improving indoor 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 thermal performance reviews.") OR ("improving poor performance measures."))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"improving thermal performance reviews.\") OR (\"improving poor performance measures.\"))".
• Removing quotes may allow a broader search: (( improving thermal performance reviews. ) OR ( improving poor performance measures. )).
• Adding a wildcard symbol may retrieve word variants: (("improving thermal performance reviews.") OR ("improving poor performance measures."))*.