Perhaps you should try some spelling variations:
"its decolonization africa" » "its democratization africa", "its colonization africa", "_ decolonization africa", "box decolonization africa"
"_ colonization failed" » "_ colonization still", "_ organizations failed", "_ decolonization failed", "decolonization _ failed"
"china cooperation history" » "china corporation history", "china federation history", "asian cooperation history", "regional cooperation history"

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 decolonization africa") OR ("_ colonization failed"))) OR ("china cooperation history"))~.
• Removing quotes may allow a broader search: (((( its decolonization africa ) or ( _ colonization failed ))) or ( china cooperation history ))~.
• Adding a wildcard symbol may retrieve word variants: (((("its decolonization africa") or ("_ colonization failed"))) or ("china cooperation history"))*.