Perhaps you should try some spelling variations:
vaccine research » medicine research
action research » national research
new action » new nation
july 2009 » july 2007, july 2019, july 2006
july 2008 » july 2013, july 2012, july 2015
july 2020 » july 2013, july 2012
aids » aims, aid

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( aids vaccine research : ((july 2009) OR (july 2008)) ) or ( new action research : july 2020 ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( aids vaccine research : ((july 2009) OR (july 2008)) ) OR ( new action research : july 2020 )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( aids vaccine research : ((july 2009) OR (july 2008)) ) or ( new action research : july 2020 ))".
• Adding a wildcard symbol may retrieve word variants: (( aids vaccine research : ((july 2009) OR (july 2008)) ) or ( new action research : july 2020 ))*.