Free images results:

Think pictures, stock photos and images


Thinker Royalty Free Stock Photos
Author: Smitea
Baboon Stock Photo
Author: Eminavn
Baboons Royalty Free Stock Photo
Author: Eminavn
Thinking Stock Photo
Author: Bandu
Discussion Royalty Free Stock Images
Author: Optox
Hobby Royalty Free Stock Photography
Author: Pilarin

Also, here are some commercial RF-licensed images that match your search criteria:  

Explore more commercial options: More Think Stock Illustrations & Vectors | More Think Stock Video Footage