Hi,
I thought it could have been Jan Zeman as this is very much like his work and still could be as there are unsigned pieces of his that are out there. Put his name in Google followed glass and you will see what I mean .
You are right in thinking that Bohemia covers a multitude of countries but theres a good chance its from some where in that region.
I'll bear you in mind should I come across another piece like yours.
Mike www..co.uk