Perhaps you should try some spelling variations:
"Improving contract performance measures." » "Improving country performance measures.", "Improving court performance measures.", "Improving economic performance measures."
improving contract » improve contract, improving central, improve contrast
"improving loan performance series." » "improving loan performance studies.", "improving loan performance size.", "improving local performance series.", "improving land performance series.", "improving lead performance series."

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("Improving contract performance measures.") OR ("improving loan performance series."))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"Improving contract performance measures.\") OR (\"improving loan performance series.\"))".
• Removing quotes may allow a broader search: (( Improving contract performance measures. ) OR ( improving loan performance series. )).
• Adding a wildcard symbol may retrieve word variants: (("Improving contract performance measures.") OR ("improving loan performance series."))*.