Perhaps you should try some spelling variations:
factor research » sector research, action research, water research
option research » opinion research, action research, operations research
multi factor » multi sector, _ multifactor, multi faceted
multi option » mali options, multiple options
june 2013 » july 2013
july 2012 » july 2013

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 factor research : june 2013 ) OR ( multi option research : july 2012 ))~.
• Adding a wildcard symbol may retrieve word variants: (( multi factor research : june 2013 ) or ( multi option research : july 2012 ))*.