Problem with PocketBook Touch Lux 2

I've bought 2 books on Google Books and dowload them as epub files and next read them at my PC with Adobe Digital Editions. I'd like to download and read them also on my PocketBook Touch Lux 2. The device is already authorized, but when I want to read both of them there are only one blank page. On my PB there is only cover visited and nothing else.

I've try to download one of this books as pdf to my PB and it's okey. But what about epub files? Second book has only that format of file and I've wanted to read it on my e-book reader, not on PC.