Problem with nginx configuration - second approach

Hello, I was trying to deal with my problem which I wrote here: https://www.digitalocean.com/community/questions/problem-with-configure-nginx-i-guess-to-cooperate-with-domain-and-not-show-ip-address

Now I have that case:

• When I put server_name domain.com www.domain.com in nginx configuration file, I see only nginx start page but with my domain name: Image 1

• When I put server_name domain.com www.domain.com ip_address in nginx configuration file, I see my webpage but with ip_address: Image 2

I think I’ve been trying everything and did everything in all guidelines. Here is my actual nginx content:

server {
    listen 80;
    server_name mydomain.com www.mydomain.com ip_address;

    location = /favicon.ico { access_log off; log_not_found off; }
    location /static/ {
        root /home/tuliokkj/my_project;
    }

    location /media/ {
        root /home/tuliokkj/my_project;
    }


location / {
        include proxy_params;
#        proxy_set_header Host karolkurek.pl;  # I tried with this line and without it
        proxy_set_header X-Real-IP $remote_addr;
        proxy_pass http://unix:/home/tuliokkj/my_project/portfolio.sock;
    }

}

Any ideas?