Perhaps you should try some spelling variations:
"improving thermal performance reviews." » "improving thermal performance review.", "improving thermal performance reports.", "improving thermal performance risks.", "improving external performance reviews.", "improving animal performance reviews.", "improving erm performance reviews."
"improve company performance reviews." » "improve company performance review.", "improve company performance reports.", "improve company performance risks.", "improve country performance reviews."

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 ("improve company performance reviews."))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"improving thermal performance reviews.\") OR (\"improve company performance reviews.\"))".
• Removing quotes may allow a broader search: (( improving thermal performance reviews. ) OR ( improve company performance reviews. )).
• Adding a wildcard symbol may retrieve word variants: (("improving thermal performance reviews.") OR ("improve company performance reviews."))*.