Assalaamu 'alaikum

Is there a difference in the way one performs the stressed and non stressed sunnah prayers?

I have read that the non stressed sunnah as is prayed in the Asr salah, when you sit for tashahhud in the 2nd rakat, you recite all the way to the end and then rise and then start the prayer with thana and ta'awudh....and also recite a surah after al fatiha in the 3rd and 4th rakat...

Is this correct?

JazakAllahu khairan.

Wassalaamu 'alaikum