Perhaps you should try some spelling variations:
"terra australie incognita" » "terra australis incognita", "terra australis cognita", "terra australias incognita", "terre australe incognita"
"terres australes incognita" » "terres australis incognita", "terres australis cognita", "terre australe incognita", "terra australis incognita", "terre australi incognita"

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: (("terra australie incognita") OR ("terres australes incognita")).
• Removing quotes may allow a broader search: (( terra australie incognita ) or ( terres australes incognita )).
• Adding a wildcard symbol may retrieve word variants: (("terra australie incognita") or ("terres australes incognita"))*.