Telex/Unikey Vietnamese keyboard in macOS High Sierra 10.13.1

Hi all,

I have just upgraded with macOS High Sierra 10.13.1 on my Macbook Air 13-inch, early 2015. And I can no longer type Vietnamese/Telex or Unikey in the same way as I used to do three hours ago.

There is no selection to tick Telex/Unikey in "Input Source" when Adding Vietnamese keyboard. In macOS High Sierra, the new Vietnamese keyboard is re-invented, solely for Macbook products, I believe. It is a hassle, because it takes away the numeric digits 1-0 while typing in this newly keyboard. So if I want to type numbers, I have to switch to US keyboard - attached picture showing this point.

My question is: Is there any approach (rather than downgrading macOS High Sierra just because of this unfamiliar keyboard) to switch back to the old version of Vietnamese keyboard?

Thank you very much!