Your country's copyright laws are different from those in the U.S., and understanding and dealing with them is up to you. If you have a book that is in the public domain in your country, but not in the U.S., it is perfectly legal for you to publish it personally there, but we can't.
Similarly, it may be legal for us to publish it here, but not for you to publish it, or perhaps even copy it, where you are.
There are organizations in other countries operating in more liberal copyright regimes that may be able to publish texts that we cannot. For example, Project Gutenberg of Australia at <http://www.gutenberg.net.au> can accept some works not eligible in the U.S.