They have different meanings. If you are open-minded, you are willing to accept new ideas about something. You might say 'I'm quite open-minded about the relocation project'. This means that you don't have strong views on the topic and that you are happy to listen other people's opinions. Broad-minded is the opposite of narrow-minded, and it means tolerant. It's usually used with reference to moral and particularly sexual issues. For example, 'Are you really going to see 'Fifty Shades of Grey' with your grandma?' 'Oh, yes, it's not a problem. She's very broad-minded'.

Open-minded is most used, at least where I'm from. They mean the same thing, but I don't hear "broad-minded" very much. Hope this helps!

Same as here in Australia, we say open-minded. I don't think I've ever heard anyone say 'broad-minded'.

I would know what is it meaning?

According to dictionaries: An open-minded person accepts new ideas.(Her/his mind is open to let in new ideas) A broad-minded person is tolerant.