Perhaps you should try some spelling variations:
"multiple opinion research : july 2007" » "multiple options research : july 2007", "multiple positions research : july 2007", "multiple decision research : july 2007", "multiple action research : july 2007", "multiple opinion research : july 2008", "multiple opinion research : july 2013", "multiple opinion research : july 2012"
"multi plants research : july 2007" » "multi class research : july 2007", "multi planning research : july 2007", "multi changes research : july 2007", "multi plant research : july 2007", "multi party research : july 2007", "multi player research : july 2007", "multi plants research : july 2008", "multi plants research : july 2013", "multi plants research : july 2012"

Try widening your search to All Fields.

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• Performing a fuzzy search may retrieve terms with similar spellings: (("multi plants research : july 2007") or ("multiple opinion research : july 2007"))~.
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