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 2012"
"multi actors research : july 2011" » "multi factors research : july 2011", "multi actions research : july 2011", "multi author's research : july 2011", "multi actor research : july 2011", "multi acteurs research : july 2011", "multi factor research : july 2011", "multi actors research : july 2013", "multi actors research : july 2012", "multi actors research : july 2015"

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("multiple options research : july 2007") or ("multi actors research : july 2011"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("multiple options research : july 2007") OR ("multi actors research : july 2011")).
• Removing quotes may allow a broader search: (( multiple options research : july 2007 ) or ( multi actors research : july 2011 )).
• Adding a wildcard symbol may retrieve word variants: (("multiple options research : july 2007") or ("multi actors research : july 2011"))*.