ISO Latin 2 named entities in HTML 4

Hello html people!

I'm not sure that this is the right place for my question, so please
accept my appologize if I go wrong.
I have a html document with javascript written in ISO Latin 2 charset.
As I can see in this document there are named entities(which I have to
use in javascript) only for a few character that I need. What should I
do for the rest, like:
c with caron
z with caron

Please, give me some advice how to solve my problem or where to look for
the answer.
Thanks in advance,

Albena