Per the duo lingo dictionary “Qua” = through, over... and Qủa is a classifier for fruit.
I couldn’t find “wow” in the DL dictionary but per Google translate wow is “ồ”.
Also played with Google translate for the different variations of “qua”
Qua = By
Qưa = Dear
Qúa = Too much
Qùa = Gifted
Qủa = Fruit
Qũa = File
Not sure if this helps but thought I would throw in my highly confused opinion, lol.