Perhaps you should try some spelling variations:
"city cooperation studies" » "city cooperation series", "city cooperation sources", "city cooperation implies", "city corporation studies", "china cooperation studies", "city corporations studies"
"_ colonization failed" » "_ colonization still", "_ organizations failed", "_ decolonization failed", "decolonization _ failed"
"pro colonization songs" » "pro colonization still", "pro colonization work", "pro decolonization notes", "bio colonization songs", "re colonization songs", "mars colonization songs"

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

• Performing a fuzzy search may retrieve terms with similar spellings: (((("city cooperation studies") or ("pro colonization songs"))) or ("_ colonization failed"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("city cooperation studies") OR ("pro colonization songs"))) OR ("_ colonization failed"))*.
• Removing quotes may allow a broader search: (((( city cooperation studies ) or ( pro colonization songs ))) or ( _ colonization failed ))*.