Perhaps you should try some spelling variations:
"multiple vaccines research : july 2013" » "multiple access research : july 2013", "multiple crises research : july 2013", "multiple faces research : july 2013", "multiple vaccine research : july 2013", "multiple practices research : july 2013", "multiple accidents research : july 2013"
"multi water research : july 2009" » "multi water resource : july 2009", "multi further research : july 2009", "multi rater research : july 2009", "multi layer research : july 2009", "multi rate research : july 2009", "multi water research : july 2008", "multi water research : july 2007", "multi water research : july 2019"

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (("multiple vaccines research : july 2013") or ("multi water research : july 2009"))~.
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• Adding a wildcard symbol may retrieve word variants: (("multiple vaccines research : july 2013") or ("multi water research : july 2009"))*.