Perhaps you should try some spelling variations:
"multiple vaccines research : july 2008" » "multiple access research : july 2008", "multiple crises research : july 2008", "multiple faces research : july 2008", "multiple vaccine research : july 2008", "multiple practices research : july 2008", "multiple accidents research : july 2008", "multiple vaccines research : july 2013", "multiple vaccines research : july 2012", "multiple vaccines research : july 2020"
"multi option research : july 2006" » "multi opinion research : july 2006", "multi action research : july 2006", "multi optics research : july 2006", "multi location research : july 2006", "multi population research : july 2006", "multi ratios research : july 2006", "multi option research : july 2007", "multi option research : july 2009", "multi option research : july 2013"

Try widening your search to All Fields.

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• Performing a fuzzy search may retrieve terms with similar spellings: (("multiple vaccines research : july 2008") or ("multi option research : july 2006"))~.
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