The online versions of Turbo Tax is only made to file one return per account. If you file more than one return using the same account, the new return will override the previous return filed. So when you login, the last return you filed will show. There is no way to access the prior returns.
Using the online editions you have to start a new account with a
new unique user ID for another tax return. The online editions are only
for completing one tax return per account and user ID - https://turbotax.intuit.com/personal-taxes/online/