So, http://domainname.com/kucingberlari will activate index.php. However, the url in the location bar is still http://domainname.com/kucingberlari and the content of $_SERVER['REQUEST_URI'] is still /kucingberlari. I can then use the content of $_SERVER['REQUEST_URI'] to decide what kind of pages need to be shown in index.php. It's the same method wordpress' permalink use.
This is a full redirection where the location of the URL in the location bar changed. Also, the content of $_SERVER['REQUEST_URI'] also changed into /index.php?keyquery=blablabla$_SERVER['REQUEST_URI']
Why if the .htaccess rewrite rule refer to a different domain it become a full redirect? I thought the flag for full redirect must be [R] but it is [L] rather than [R]