Access Sioyek's text version of PDF page

[SuperCowProducts]

I wanted to search for a formula I found on the page of a PDF, although the text I copied didn't work for searching (although it corresponded to what I saw with pdftotext, i.e. Vout>Vin): is there a way to see how Sioyek has indexed the page? That way I can use a string Sioyek recognises to perform this search if that makes sense.

For now I have just been using Okular: the search is a lot slower, but it can get this particular job done.

[UPDATE] I copied the string I searched for in Okular in the terminal and it revealed it contained a newline character, maybe Sioyek search doesn't handle newlines?

[ahrm]

Can't you just select the text and copy it?

[SuperCowProducts]

So in Okular it copies, but in Sioyek it looks like the fraction gets split into multiple lines (or maybe layers?), so it loses this ability.

[UPDATE] I tried copying multiline text (code) from another PDF, and it looks like Sioyek is unable to copy newlines like Okular can.