Q:

MariaDB 10.0.33 Configuring MariaDB for Remote Client Access

I just keep verbatim the instructions in MariaDB docs but it does not work at all, and I wast a great ammount of time. 
MariaDB docs does not take into account this version in its documentation. 
Following the instructions i modified the file my.cnf that in my case it was /etc/mysql/my.cnf
I comment this out as the example, but in my case I had to add it manually. 
 [mysqld]
    ...
    #skip-networking
    ...
    #bind-address = <some ip-address>
    ...

And as I already have an account with remote permissions, I just restarted the mysql service but nothing happened. 
Check if por is open
sudo nmap -PN -p 3306 -sV server_ip

The port wasn't listening from remote ips. 

A:

English
The answer was already in the file my.cnf where it explains the configuration order so that the last file is the one that applies. 
The problem I got is that the MariaDB docs recommends to comment out the lines skip-networking and bind-address. 
In my case, to comment out lines does nothing, it doesn't override the previous configuration, because it only applies if it defines something new, so I had to go to the source where it was defined that keywords to comment that out in the first place. 
I had to comment out this file /etc/mysql/mariadb.conf.d/50-server.cnf where it was firstly defined skip-networking and bind-address. 
/etc/mysql/my.cnf
# The MariaDB configuration file
#
# The MariaDB/MySQL tools read configuration files in the following order:
# 1. " /etc/mysql/mariadb.cnf" (this file) to set global defaults,
# 2. " /etc/mysql/conf.d/*.cnf" to set global options. 
# 3. " /etc/mysql/mariadb.conf.d/*.cnf" to set MariaDB-only options. 
# 4. " ~/.my.cnf" to set user-specific options. 
#
# If the same option is defined multiple times, the last one will apply. 
...

I hope this could save time to someone else.