Perhaps you should try some spelling variations:
cooperative studies » comparative studies, cooperation studies, cooperative strategies
colonization israel » communication israel, colonization still, colonization history
early cooperative » early cooperation, early postoperative, dairy cooperative
its colonization » anti colonization, jews colonization, mars colonization
pro colonization » bio colonization, re colonization, mars colonization

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

• Performing a fuzzy search may retrieve terms with similar spellings: (((( early cooperative studies ) or ( its colonization _ ))) or ( pro colonization israel ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((( early cooperative studies ) OR ( its colonization _ ))) OR ( pro colonization israel )).
• Adding a wildcard symbol may retrieve word variants: (((( early cooperative studies ) or ( its colonization _ ))) or ( pro colonization israel ))*.