Perhaps you should try some spelling variations:
"multi factor research : july 2012" » "multi factors research : july 2012", "multi sector research : july 2012", "multi actors research : july 2012", "multi actor research : july 2012", "_ multifactor research : july 2012", "multi factor research : july 2013"
"multi option research : june 2011" » "multi opinion research : june 2011", "multi action research : june 2011", "multi optics research : june 2011", "multi location research : june 2011", "multi population research : june 2011", "multi ratios research : june 2011", "multi option research : june 2013", "multi option research : june 2014", "multi option research : june 2010"

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