available fonts don´t show Czech lang letter right

Hi there,

I found a nice fitting template for my web and started to fill it out. However soon I started to see a problem - the page shall be in Czech language and all fonts have a massive problem with its special characters. They don´t show special letters correctly - in particular letters like ščřžěéňůú and their capital versions. Is there any trick how to solve this? I Changing the font does not help. Maybe change a system unicode to UTF-8 or something universal covering all these symbols? Thanks.