Not if you account for variations of pronunciation in dialects. Not even the most phonetically accurate accent, the Hanoian Northern accent which I am a native speaker of, is perfect.
For example, you could hear Northern Vietnamese people say "dổ", "dá" instead of "rổ", "rá". Morning dew is pronounced "xương" but is written as "sương". These characters are pronounced with greater clarity in the Central and Southern regions, but they have their own peculiarities too. Til' this day I still find it iffy they call someone named "Diễm" as "Yỉm". Unless you have seen the correct way to spell those words before, you can't say for sure. Even now as a working adult I find myself referring to the dictionary to make sure my accent doesn't embarrass me in official emails.
In a perfect world, we can have one single Vietnamese accent that aims to pronoun all these words true to the intended way of the alphabet, but it isn't practical. That being said, one can get pretty far in Vietnamese when encountering new words.