[Setsuna doesn't want to mark the documents. But the repeating clusters almost beg to be highlighted or something. She starts copying the words onto a scratch of paper instead.]

Ancient civilizations often would copy scrolls by hand since there was no method to print copies otherwise. These could be translations across the years or even just regional differences. It would explain the slight deviations but the pattern remaining the same.

[She finishes writing the passages out on her paper, each repeated passage now spaced apart on her paper. She's not sure if that will help or not, but it makes it easier to compare now that they are all on the same piece of paper to examine.]