Perhaps you should try some spelling variations:
"improving logistics performance contracts." » "improving cognitive performance contracts."
"improving basic performance based." » "improving based performance based.", "improving bank performance based.", "improving past performance based.", "improving basic performance measures.", "improving air performance based.", "improve basic performance based.", "improving public performance based."

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

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