Perhaps you should try some spelling variations:
"multi accident research : july 2012" » "multi current research : july 2012", "multi recent research : july 2012", "multi vaccine research : july 2012", "multi client research : july 2012", "multi accident research : july 2013"
"multi factor research : june 2011" » "multi factors research : june 2011", "multi sector research : june 2011", "multi actors research : june 2011", "multi actor research : june 2011", "_ multifactor research : june 2011", "multi factor research : june 2013", "multi factor research : june 2014", "multi factor research : june 2010"

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("multi factor research : june 2011") OR ("multi accident research : july 2012"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"multi factor research : june 2011\") OR (\"multi accident research : july 2012\"))".
• Removing quotes may allow a broader search: (( multi factor research : june 2011 ) OR ( multi accident research : july 2012 )).
• Adding a wildcard symbol may retrieve word variants: (("multi factor research : june 2011") OR ("multi accident research : july 2012"))*.