Perhaps you should try some spelling variations:
"multiple vaccines research : july 2009" » "multiple access research : july 2009", "multiple crises research : july 2009", "multiple faces research : july 2009", "multiple vaccine research : july 2009", "multiple practices research : july 2009", "multiple accidents research : july 2009", "multiple vaccines research : july 2008", "multiple vaccines research : july 2007", "multiple vaccines research : july 2019"
"basin climate research : july 2009" » "based climate research : july 2009", "asia climate research : july 2009", "baseline climate research : july 2009", "basin climate research : july 2008", "basin climate research : july 2007", "basin climate research : july 2019"

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("multiple vaccines research : july 2009") or ("basin climate research : july 2009"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("multiple vaccines research : july 2009") OR ("basin climate research : july 2009")).
• Removing quotes may allow a broader search: (( multiple vaccines research : july 2009 ) or ( basin climate research : july 2009 )).
• Adding a wildcard symbol may retrieve word variants: (("multiple vaccines research : july 2009") or ("basin climate research : july 2009"))*.