Help! I'm getting weird-russian-non-related-to-the-topic comments on my website posts!

Hi! I don't know if it's just me but it's been a year now since i made my wordpress website and i get so many weird russian comments that are not related with my posts. How can i get rid of these? Is this normal or should i install some filtering apps? Also, some of the comments are english but they advertise some links that i think are scam. Hoping that someone can help me with these. Thanks!