Perhaps you should try some spelling variations:
"_ decolonization africa" » "_ democratization africa"
"trade organizations fad" » "trade organization fad", "trade organizations a", "trade organizations can", "trade organizations d.d"
"et cooperation history" » "et corporation history", "et federation history", "et cooperations history", "eu cooperation history", "2 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: (((("_ decolonization africa") OR ("trade organizations fad"))) OR ("et cooperation history"))~.
• Removing quotes may allow a broader search: (((( _ decolonization africa ) or ( trade organizations fad ))) or ( et cooperation history ))~.
• Adding a wildcard symbol may retrieve word variants: (((("_ decolonization africa") or ("trade organizations fad"))) or ("et cooperation history"))*.