Perhaps you should try some spelling variations:
"improving country performance contracts." » "improving voluntary performance contracts.", "importing country performance contracts.", "improving community performance contracts."
"improve water performance contract." » "improve rate performance contract.", "improve rated performance contract.", "improve rates performance contract.", "improving water performance contract."

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

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