Google fonts needs extended character sets (extended latin)

Hi!
Google fonts are imported only with the basic character set.
We need extended characters (extended latin) to show texts correctly.

code from my website:

@import url(http://fonts.googleapis.com/css?family=Oswald:300|Oswald:300|Oswald:700);

code generated from google fonts with extended character set:

@import url(http://fonts.googleapis.com/css?family=Oswald:300&subset=latin,latin-ext);

I try something with importing code to custom css, but nothing happens :(
Please help.
Thanks!