The Vietnamese alphabets are listed in several noncontiguous Unicode ranges:

Basic Latin {U+0000..U+007F}
Latin-1 Supplement {U+0080..U+00FF}
Latin Extended-A, -B {U+0100..U+024F}
Latin Extended Additional {U+1E00..U+1EFF}
Combining Diacritical Marks {U+0300..U+036F}

'CJK' == 4E00-9FFF