Did you ever find a solution to your problem? I have some dense ebooks with repeating terms related to different applications so I've been trying to figure out how to do boolean or regular expression searches within a text (I suppose within sentences... or paragraphs.), but haven't found anything good yet. I guess I can figure out how to use grep with them, but it'd be nice if there were some sort of ebook viewer that allowed for easily doing this kind of search... Find anything?.
Cheers.