Perhaps you should try some spelling variations:
scientific collaboration » scientific communication, scientific explanation, scientific computation
scientific exploration » scientific explanation, scientific application, scientific information
african voyagers » african managers, african teenagers, african voices

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: (( european AND african voyagers of scientific exploration ) OR ( european AND african voyagers of scientific collaboration )).
• Adding a wildcard symbol may retrieve word variants: (( european and african voyagers of scientific exploration ) or ( european and african voyagers of scientific collaboration ))*.