Perhaps you should try some spelling variations:
"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 2008", "multi option research : july 2007", "multi option research : july 2009"
"multi labor research : july 2006" » "multi water research : july 2006", "multi prior research : july 2006", "multi layer research : july 2006", "multi label research : july 2006", "multi factor research : july 2006", "multi labor research : july 2008", "multi labor research : july 2007", "multi labor research : july 2009"

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

• If you are trying to use Boolean operators, they must be ALL CAPS: (("multi option research : july 2006") OR ("multi labor research : july 2006"))~.
• Removing quotes may allow a broader search: (( multi option research : july 2006 ) or ( multi labor research : july 2006 ))~.
• Adding a wildcard symbol may retrieve word variants: (("multi option research : july 2006") or ("multi labor research : july 2006"))*.