Did you e-file?

https://turbotax.intuit.com/tax-tools/efile-status-lookup/

TurboTax gives you an estimated date for receiving your refund based on a 21 day average from your date of acceptance, but it can take longer.

Once your federal return has been accepted by the IRS, only the IRS has any control. TurboTax does not receive any updates from the IRS. Your ONLY source of information about your refund now is the IRS.

You need your filing status, your Social Security number and the exact amount  (line 20 of your Form 1040) of your federal refund to track your Federal refund:   

https://www.irs.gov/refunds

To track your state refund:    

https://ttlc.intuit.com/questions/1899433-how-do-i-track-my-state-refund

On the IRS site you are also offered the use of an app called IRS2Go

https://ttlc.intuit.com/questions/1901548-why-do-some-refunds-take-longer-than-others

If you chose to have your TurboTax fees deducted from your federal refund, that will take some extra time, while the third party bank handles the refund processing.

https://www.irs.gov/refunds/tax-season-refund-frequently-asked-questions

https://ttlc.intuit.com/questions/2840013-does-accepted-mean-my-refund-is-approved

https://ttlc.intuit.com/questions/2724106-my-return-is-accepted-but-still-not-approved-is-there-a-pr...

You can check your status using the IRS Where’s My Refund? tool. You will not be able to start checking the status of your tax refund for 4 weeks if you mail a paper tax return.

I filed it online. But i am expecting the return through the mail

No matter how you chose to receive your refund you can track it and see when the IRS releases it by using the IRS site.  If you are having it mailed to you then obviously after the IRS puts it in an envelope you have to allow some days for it to get to you in the mail.  The mail it first class mail--no tracking for the envelope.

The IRS says: 

Where's My Refund?

Check the status of your refund online within 24 hours after we receive your e-filed return

Please click on the blue link above. Once they release/mail your refund on the date given, the post office has two weeks to deliver your refund check.

If you do not receive it after 2 weeks, call the IRS at 800-829-1040.