If you used the TurboTax Home & Business CD/Download software installed on your computer to prepare and file that 2016 return and saved as a PDF or tax data file to your computer, that is the only place it's stored. TurboTax does not save copies online when you used the CD/Download version of the software. Only returns prepared and filed in TurboTax Online are stored in your online account.
How do I get a copy of a tax return prepared with the TurboTax CD/Download software?