Select steam languages

Good day, dear developers! Why can’t I choose Russian on Steam? Because of this, my mod doesn’t work with taunts: since the basic language is English, the voice-over will only be available when English is enabled in the game, as in this video, but my mod is for Russian taunts(

Please make a selection of all languages, but if there are no voice-overs or videos with the selected language, let the videos and sounds be uploaded in English)))