Perhaps you should try some spelling variations:
option research » opinion research, action research, operations research
water research » water resource, further research
multi option » mali options, multiple options
multi water » multi partner, multi factor
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 water research : june 2013 ) OR ( multi option research : july 2012 ))~.
• Adding a wildcard symbol may retrieve word variants: (( multi water research : june 2013 ) or ( multi option research : july 2012 ))*.