Perhaps you should try some spelling variations:
"prime minister of Czechoslovakia" » "primer minister of Czechoslovakia", "price minister of Czechoslovakia", "crime minister of Czechoslovakia"
"prime ministers of czechoslovakia" » "primer ministers of czechoslovakia", "price ministers of czechoslovakia", "crime ministers of czechoslovakia"

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: (("prime minister of Czechoslovakia") OR ("prime ministers of czechoslovakia")).
• Removing quotes may allow a broader search: (( prime minister of Czechoslovakia ) or ( prime ministers of czechoslovakia )).
• Adding a wildcard symbol may retrieve word variants: (("prime minister of Czechoslovakia") or ("prime ministers of czechoslovakia"))*.