Question: iPad books not in iPhone 8
I have these two devices, both with updated iOS (11.2.6). The question arises because I have several epubs in the iBooks library on the iPad (mini 4) that I have added using iTunes, but those books do not appear in iPhone iBooks. I have checked the configuration of both devices and have iCloud Drive activated and iBooks synchronization, but they do not appear ... I only see the downloaded ones from the Store. Interestingly, if I send the epub that I am reading by mail and I copy it in iBooks of the iPhone, it synchronizes with the last page read on the iPad. The fact of loading them on the iPad using iTunes is to put them on the cover and leave them "pretty". Can someone guide me? What am I doing wrong?
Thank you in advance for your help
iPhone 8, iOS 11.2.6