Team figth

Hi, I palay dota 2 about 4 month.
I have big problem in team fights, for example i cant find my hero in the middle of the fihgt and after few seconds i find out i'm dead. :P
Usually i die first in team fights,so i'd be grateful if someone culd give me some advice about that.

You'll just have to get used to it, things get graphically messy in teamfights.

However, one important thing to note is that you have to know what exactly is your role in teamfights. Are you an initiator? Get in first. If you give your team an advantage, then even if you die you've done well. Are you a carry? Your job is to right click, disable if you have one, and most importantly being the person with the damage to take down all of the heroes on the other side AND survive.

The point here is know your goal and fulfill it. If you can, dying is fine.

Sooner or later, you'll know all the spells, all the heroes, you'll know what's your role in the team and also your positioning. Don't worry about it, you'll get used to it. :)

Focus Drow Ranger, Huskar, or any hero with 2 lives, like Skeleton King or someone who picked up Aegis of the Immortal.

Just kill the carry.

Hades is spot on, it takes experience. Normally yes, kill the carry first. Unless there is a Dazzle or Chen floating around. Or that warlock who wants to drop his ult on your team. Better get that silencer as well so we can spam spells.

It's one of those things that game by game. Learn your role (disabler, initiator, DPS, healer) and decide from that
Chen should never be the first one in unlike Magnus who should setup the whole team fight.

Gl, keep playing

Given you have enough disables, I find it generally better to kill their AOE initiator first while keeping the carry disabled, as those are ultimately the most dangerous. Carry comes second.

I.E: That Earthshaker is more dangerous than a Drow Ranger.