Perhaps you should try some spelling variations:
"multi option research : july 2006" » "multi opinion research : july 2006", "multi optics research : july 2006", "multi actions research : july 2006", "multi location research : july 2006", "multi population research : july 2006", "multi ratios research : july 2006", "multi option research : july 2008", "multi option research : july 2007", "multi option research : july 2009"
"multi action research : july 2019" » "multi national research : july 2019", "multi actor research : july 2019", "multi location research : july 2019", "multi factor research : july 2019", "multi action research : july 2013", "multi action research : july 2012", "multi action research : july 2015"

Try widening your search to All Fields.

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• Performing a fuzzy search may retrieve terms with similar spellings: (("multi option research : july 2006") or ("multi action research : july 2019"))~.
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