No improvement in deadlifts

Hello fellow gymbros,

I got superb suggestion from here last time to improve squat. So I thought I’ll just ask for deadlifts as well.

I’ve been deadlifting this same weight from more than an year i.e 120kgs (50x2 + 20) for 12 reps. I’m able to do 130kgs as well but it sucks the soul out of me and sometimes gives a minor blackout as well. I’ve seen people deadlifting 200kgs online like it’s nothing. So I seriously want to improve my deadlift as well.

I got the flat weightlifting shoes as well to help with the form but it doesn’t seem to help much. Can anyone please point out what I might be doing wrong here? Any suggestions and criticism is very welcome. Feel free to point out any mistakes or minor improvements that can help me.

Thanks 🙏🏻