дозна́ться (Russian) comes from Russian зна́ть, from Old Russian знати, from Proto-Slavic znati, from Proto-Balto-Slavic źnōˀtei, from Proto-Indo-European ǵnéh₃t, from Proto-Indo-European ǵneh₃- — to know.
дозна́ться (Russian): to find out, to inquire (about)