i cant sync ibook epub to ipad and iphone

The iBooks app only syncs content you get from the iBooks Store. Anything else has to be synced through iTunes.

Thanks, I found if you email the book to a device, iBooks will then open the file. Thanks for the info.

I have serious problems when I sync Books, from my MacBook Pro and my iPad, frome the iTunes. I have El Capitan, and OS 9.2.1 systems in my device.

1 - I have 3200 books in epub (not from iBooks Store, but without DRM); and all of them are readable from iBooks in my MacBook

2 - The same quantity of books are in the folder Books (in the Library).

3 - When I try to sync to my iPad, through the iTunes, I select Sync All (the number of books is the same that I have in the folder Books, and in iBooks); the option Selected Books doesn't always show all the books that I really have (normally shows less).

4 - The sync apparently works, but when open iBooks in my iPad not all the book were synced.

Sorry for disturbing, but do you know what should I do???. I think there's a problem of settings or in the process of syncing itself, but I'm not able to resolve.

Many thanks

Gerardo Garcia Gorostidi