Are you using the Online browser version or the Desktop CD/Download program? They are different. When you go to Turbo Tax is the FILE menu at the top? The Desktop program does not have a menu going down the left side in black. The Desktop menus go across the top.
Are you looking for a prior year return? If you used the Desktop CD/Download program then the only copy is on your computer and not saved or stored online. So you need to make and keep your own backups.
Or request a transcript from the IRS
https://www.irs.gov/individuals/get-transcript
