Not all information that feeds into a tax return ends up in the final PDF - there's often supporting information etc that is included in the .tax file that is not in the PDF.
If you have the .tax file from 2017, you are able to transfer the data into TurboTax Online from the .tax file (though you can only do it at the beginning of the process). To do so, once you are in the tax return, click the Tax Tools button on the left hand side, then click Tools below that.
In the Tools Center popup (see screenshot) click the "Transfer last year's TurboTax return from your computer" link.
