I can benefit from tax treaty exemption. How to submit(efile) form 8833 using the software?

You will not be able to e file your return.  

For the tax treaty: First, you have to report your full income. Then you can enter the treaty exempt amount as negative income under "less common income". You will have to file form 8833 to claim an exception.  You can use Turbotax to prepare your return, but you need to print it  and mail the return along with the form 8833. 

It would depend on what form you're filing Form 8833 with.

Please see the IRS' Where to File Tax Returns - Addresses Listed by Return Type for guidance.

FOR YEARS, TURBO-TAX DOESN'T INCLUDE FORM 8833.

IT SEEMS , TO ME, THAT THERE IS A DEMAND FOR THE FORM 8833.

DOES TURBO-TAX BELIEVE THAT IT IS EASIER, FOR THEIR CUSTOMERS,TO  PRINT A SECOND COPY, GO TO THE POST OFFICE, WAIT IN LINE AND ADD ADDITIONAL  MONEY FOR POSTAGE, RATHER THAN PRESS ONE KEY TO E-FILE?