Perhaps you should try some spelling variations:
"de communication united" » "de telecommunication united", "mobile communication united", "online communication united"
"early cooperation studies" » "early cooperation series", "early cooperation sources", "early cooperation implies", "early operation studies", "early cooperative studies", "energy cooperation studies"
"its colonization still" » "its colonization failed", "its colonization israel", "its colonization songs", "anti colonization still", "jews colonization still", "mars colonization still"

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: (("de communication united") OR ((("early cooperation studies") OR ("its colonization still"))))~.
• Removing quotes may allow a broader search: (( de communication united ) or ((( early cooperation studies ) or ( its colonization still ))))~.
• Adding a wildcard symbol may retrieve word variants: (("de communication united") or ((("early cooperation studies") or ("its colonization still"))))*.