Perhaps you should try some spelling variations:
"multiple solutions research : july 2009" » "multiple resolution research : july 2009", "multiple situations research : july 2009", "multiple locations research : july 2009", "multiple relations research : july 2009", "multiple pollution research : july 2009", "multiple solutions research : july 2008", "multiple solutions research : july 2007", "multiple solutions research : july 2019"
"multiple opinion research : july 2012" » "multiple options research : july 2012", "multiple positions research : july 2012", "multiple decision research : july 2012", "multiple action research : july 2012", "multiple opinion research : july 2013"

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

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• Adding a wildcard symbol may retrieve word variants: (("multiple solutions research : july 2009") or ("multiple opinion research : july 2012"))*.