Do you mean you want the downloaded desktop software for 2017 and 2018?
For2018
https://turbotax.intuit.com/personal-taxes/cd-download/
For 2017
https://turbotax.intuit.com/personal-taxes/past-years-products/
Trying to get what? The software to prepare returns for 2017 and 2018? Or copies of returns you already filed for those years? When you add on to someone else's thread, you have to ask your question clearly--we do not know what you want.
PRINT RETURN You need to print a copy of your return? Sign in to your account using exactly the same account and user ID that you used to prepare your return.
On the bottom of the screen find Your tax returns & documents and click on Show. Click on the Year and Click on Download/print return (PDF)
https://ttlc.intuit.com/questions/3404575-how-do-i-access-my-prior-year-2017-return
You can get a free transcript from the IRS: