Đó means like far but not that far.
Kia means very far
If wrong blame my vietnamese teacher
because kia makes less sense, and do means that is her and day would mean this is her
"That is her " is idiomatic but grammatically inconsistent with the rule that the verb "to be " takes a predicate nominative. "That is she" is correct, grammatical and actually used in speech. "That is her " has been called a "sturdy indefensible " because it is so resistant to correction in colloquial speech.
Why the minus 2? I answered as I was taught in school. "It is she" is and always has been correct. Some people even say ít in conversation. I usually do not but in an exercise I tried to be proper, only to be told that the grammatical answer was incorrect. DL should not be rejecting perfectly good English.
As i figured it out..kia has to be used for things or persons close to the speaker ( not emotionally i think
As a native speaker of (Middle Atlantic) American English I would say, "That is she" as often as "That is her."
"That is she" sounds strange and formal? "That is her" is correct as well. It sounds more casual