Perhaps you should try some spelling variations:
"nigerian languages" » "iberian languages", "german languages", "indian languages"
"nigeria language" » "sumerian language", "media language", "india language"
"bulgare langue" » "bulgarie langue", "vulgare langue", "bulgarien langue"

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: (("bulgare langue") OR ((("nigeria language") OR ("nigerian languages")))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"bulgare langue\") or (((\"nigeria language\") OR (\"nigerian languages\"))))".
• Removing quotes may allow a broader search: (( bulgare langue ) or ((( nigeria language ) OR ( nigerian languages )))).
• Adding a wildcard symbol may retrieve word variants: (("bulgare langue") or ((("nigeria language") OR ("nigerian languages"))))*.