Perhaps you should try some spelling variations:
"_ decolonization failed" » "_ colonization failed", "_ decolonization case", "_ decolonization africa", "decolonization _ failed"
"its cooperation studies" » "its cooperation series", "its cooperation sources", "its cooperation implies", "city cooperation studies", "et cooperation studies", "its corporation studies"
"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.

• If you are trying to use Boolean operators, they must be ALL CAPS: (((("its cooperation studies") OR ("pro colonization songs"))) OR ("_ decolonization failed"))~.
• Removing quotes may allow a broader search: (((( its cooperation studies ) or ( pro colonization songs ))) or ( _ decolonization failed ))~.
• Adding a wildcard symbol may retrieve word variants: (((("its cooperation studies") or ("pro colonization songs"))) or ("_ decolonization failed"))*.