When a form is submitted to a PHP script, show only blank page then look into apache error log using tail command show an error, Input Variables Exceeded.

tail -f /var/log/httpd/error.log
[Mon Mar 09 12:37:05 2015] [error] [client] PHP Warning:  Unknown: Input variables exceeded 1000. To increase the limit change max_input_vars in php.ini. in Unknown on line 0,

On PHP have set  to max_inptut_vars=1000, So it's not enough to count and execute fields. Increase the values on php.ini configure file.

Find the php files,
# whereis php
php: /usr/bin/php /usr/lib/php.ini /usr/lib/php /usr/local/bin/php /usr/local/lib/php.ini /usr/local/lib/php /usr/local/lib/php.ini,v /usr/include/php

Open a php configure file php.ini
# vim  /usr/local/lib/php.ini
max_input_vars value change to 2000.

max_input_vars = 1000
max_input_vars = 2000
Finally, restart your apache server.
# /etc/init.d/httpd restart