Perhaps you should try some spelling variations:
"improving larval performance contract." » "improving larval performance contracts.", "improving level performance contract.", "improving thermal performance contract.", "improving maximal performance contract.", "improving local performance contract.", "improving legal performance contract.", "improving land performance contract."
"improving firms performance series." » "improving firms performance studies.", "improving firms performance size.", "improving firm performance series.", "improving firm performances series.", "improving funds performance series.", "improving farmers performance series.", "importing firms performance series.", "improving air performance series."

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• Performing a fuzzy search may retrieve terms with similar spellings: (("improving larval performance contract.") or ("improving firms performance series."))~.
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