Text is present but invisible

I added Kami to my google drive so I could start using its features on two pdf’s I had already been allowed as single pages from an ebook. I can open these pdf’s in a browser or other pdf apps, but when I opened them in Kami on google drive the text did not appear. I can apparently find words and such, but I only see them highlighted and never see the words. What is going on? is this a permissions thing because the document has watermarked permissions info along the border of the document?