How to change font in Joomla template?

Question

css

Hello.
I change the font in the Joomla template settings to Google Open Sans or Roboto, which have Cyrillic support. But for some reason, the font is used only for numbers and Latin, the browser imposes a standard font on the entire Cyrillic alphabet (in my opinion, Arial). Through the developer tool, if you view any piece of text, you can see that the required font is applied to it in the styles, and in source it can be seen that the font is loaded from Google.
Question: why is my left font displayed?

Answer 1

In css I added the font &subset=latin,cyrillic-ext' to the import line, Cyrillic would not load without it.

@import 'https://fonts.googleapis.com/css?family=Ubuntu:400,300&subset=latin,cyrillic-ext';