How to configure DNS of OpenVPN client?

I managed to fix it, what I did was

cd /etc/yum.repos.d
sudo wget https://copr.fedorainfracloud.org/coprs/macieks/openresolv/repo/epel-7/macieks-openresolv-epel-7.repo
sudo yum update
sudo yum install openresolv

it will create /etc/resolv.conf

then I modified it to set my custom DNS

# Generated by NetworkManager
search Home
nameserver 8.8.8.8
nameserver 8.8.4.4

client

client
tls-client
ca ca.crt
cert i7box.crt
key i7box.key
tls-crypt myvpn.tlsauth
proto tcp
remote x.x.x.x 1194 tcp
dev tun
topology subnet
cipher AES-256-CBC
log /var/log/openvpn.log
pull

also I desabled the automatic DNS and I put static ones, if you know a better method let me know

GUI static DNS