Perhaps you should try some spelling variations:
"multi option research : july 2009" » "multi opinion research : july 2009", "multi action research : july 2009", "multi optics research : july 2009", "multi location research : july 2009", "multi population research : july 2009", "multi ratios research : july 2009", "multi option research : july 2008", "multi option research : july 2007", "multi option research : july 2019"
"multi option research : july 2013" » "multi opinion research : july 2013", "multi action research : july 2013", "multi optics research : july 2013", "multi location research : july 2013", "multi population research : july 2013", "multi ratios research : july 2013"

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("multi option research : july 2009") OR ("multi option research : july 2013"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"multi option research : july 2009\") OR (\"multi option research : july 2013\"))*".
• Removing quotes may allow a broader search: (( multi option research : july 2009 ) OR ( multi option research : july 2013 ))*.