Perhaps you should try some spelling variations:
scientific application » scientific applications, scientific publications, scientific explanation
scientific exploration » scientific explanation, scientific collaboration, scientific information
american voyages » american villages, aerial voyages, american images
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 ((american voyages) OR (african voyagers)) of scientific exploration\") or (\"european AND ((american voyages) OR (african voyagers)) of scientific application\"))".
• The words AND, OR and NOT may confuse the search; try adding quotes: "\"((\\"european and ((american voyages) OR (african voyagers)) of scientific exploration\\") or (\\"european and ((american voyages) OR (african voyagers)) of scientific application\\"))\"".
• Removing quotes may allow a broader search: (( european and ((american voyages) OR (african voyagers)) of scientific exploration ) or ( european and ((american voyages) OR (african voyagers)) of scientific application )).