Swiftkey should not treat all words as Vietnamese when on its input method (TELEX)

I'm using Swiftkey's Vietnamese Telex input, there is a bit confused when typing English on it.

It treats all my word as vietnamese, so there are problems with it, for example

I must type WORRD to be correct as WORD, but WO is not a Vietnamese word, why do Swiftkey add the ? on top of O when i type R (WỎ), this is a waste of time.

Type GOOGLE.C and then O will make the word become GÔGLE.CO, what? there is not way to discard the Ô if i type O again

COORDINATE, if i remove letter by letter from the right to COOR, when remove R, it become CỎO, what again?