How I can stop the DNS server to transfer directly to my website when access phpmyadmin
Solution 1:
Assuming apache is your webserver, with centos-like configuration, the "regular" behavior, for non-hostname qualified urls, is to (try to) serve it according to the "main" webserver definition, then according to whatever virtualhost is found first in configuration. If that does not suit you, you'll have to change the alias for phpmyadmin in one/all of your vitualhosts and invoke the proper hostnam-qualified url OR change the alias for the main webserver (usually defined in /etc/httpd/conf.d/phpMyAdmin.conf)