Thank you pdurrant
But it didn't help me, any idea?
when i get diff from my ebook and one of calibre ebook (mobi) in headers
There is an attribute "Extra Record Data Flags"
(
https://wiki.mobileread.com/wiki/MOBI#MOBI_Header) in mobi header
That for calibre is "1". This attribute is important? and it can be the problem?