Were you using online TurboTax or were you using the CD/download? If you were using the CD/download then your return is stored only on the computer you used to work on it when you began; it is not stored online. The tax file is stored only on your own hard drive. Installing/downloading the software to another computer does not move your tax file to the new computer.
https://ttlc.intuit.com/questions/1901659-find-your-tax-data-file-in-mac
https://ttlc.intuit.com/questions/1900721-find-your-tax-data-file-tax-file-in-windows
If you were using online TurboTax, it does not matter that you changed computers. You just need to use exactly the same account and user ID to access your return.
Many people have multiple TT accounts and forget how to access them. Log out of the account you are in now.
https://ttlc.intuit.com/questions/1901535-forgot-your-turbotax-online-user-id-or-password
Or did you use the desktop version of TurboTax? If so, the files are on your own hard drive or any backup device you used like a flash drive.
https://ttlc.intuit.com/questions/1901486-how-many-turbotax-accounts-do-i-have