Perhaps you should try some spelling variations:
"improving poor performance reviews." » "improving poor performance review.", "improving poor performance reports.", "improving poor performance risks.", "improving sector performance reviews.", "improving power performance reviews.", "improving food performance reviews.", "improving peer performance reviews."
"improving transit performance _." » "improving transport performance _.", "improving trade performance _.", "improving plant performance _.", "improving paratransit performance _.", "improving transitions performance _."

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

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