Perhaps you should try some spelling variations:
"multiple options research : july 2007" » "multiple locations research : july 2007", "multiple positions research : july 2007", "multiple solutions research : july 2007", "multiple actions research : july 2007", "multiple optics research : july 2007", "multiple operations research : july 2007", "multiple options research : july 2008", "multiple options research : july 2013", "multiple options research : july 2020"
"multi past research : july 2012" » "multi art research : july 2012", "multi impact research : july 2012", "multi first research : july 2012", "multi party research : july 2012", "multi plant research : july 2012", "multi page research : july 2012", "multi past research : july 2013"

Try widening your search to All Fields.

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("multi past research : july 2012") or ("multiple options research : july 2007"))~.
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• Adding a wildcard symbol may retrieve word variants: (("multi past research : july 2012") or ("multiple options research : july 2007"))*.