Perhaps you should try some spelling variations:
"african students" » "american students", "african states", "indian students"
"african studies" » "american studies"
"africa studies" » "africa student"

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: (((("africa studies") OR ("african students"))) OR ("african studies")).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"africa studies\") OR (\"african students\"))) or (\"african studies\"))".
• Removing quotes may allow a broader search: (((( africa studies ) OR ( african students ))) or ( african studies )).
• Adding a wildcard symbol may retrieve word variants: (((("africa studies") OR ("african students"))) or ("african studies"))*.