Perhaps you should try some spelling variations:
"multiple options research : june 2011" » "multiple imputations research : june 2011", "multi option research : june 2011", "multiple operations research : june 2011", "multiple action research : june 2011", "multiple opinion research : june 2011", "multiple options research : june 2013", "multiple options research : june 2014", "multiple options research : june 2008"
"multi factor research : june 2012" » "multi sector research : june 2012", "multi action research : june 2012", "multi water research : june 2012", "_ multifactor research : june 2012", "multi faceted research : june 2012", "multi factor research : june 2013", "multi factor research : june 2014", "multi factor 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 factor research : june 2012") or ("multiple options research : june 2011"))~.
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