Perhaps you should try some spelling variations:
"multi national research : july 2009" » "multi educational research : july 2009", "_ multinational research : july 2009", "multinationals _ research : july 2009", "_ multinationals research : july 2009", "multi national research : july 2013", "multi national research : july 2012", "multi national research : july 2011"
"multiple options research : july 2006" » "multiple imputations research : july 2006", "multi option research : july 2006", "multiple operations research : july 2006", "multiple action research : july 2006", "multiple opinion research : july 2006", "multiple options research : july 2013", "multiple options research : july 2012", "multiple options research : july 2011"

Try widening your search to All Fields.

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• Performing a fuzzy search may retrieve terms with similar spellings: (("multiple options research : july 2006") or ("multi national research : july 2009"))~.
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