为什么.htaccess没有路由到我的index.php？

I have created .htaccess with content of:

Options +FollowSymLinks
IndexIgnore */*
# Turn on the RewriteEngine
RewriteEngine On
#  Rules
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . index.php

So, I am expecting: http://mydomain.com/command/paramater1 to be directed to index.php, but that dose not happen, instead, I get 404 error.

However, http://mydomain.com will open index.php

The directory of my website looks like this:

public_html/index.php public_html/.htaccess

I have mod_rewrite enabled.

Any idea?

EDIT

What I am expecting when http://mydomain.com/command/paramater1 is to read the command in the url in index.php and act accordingly, but as I mentioned, index.php is not opened, instead 404 error

<IfModule mod_rewrite.c>
    Options -MultiViews

    RewriteEngine On
    #RewriteBase /path/to/app
    RewriteCond %{REQUEST_FILENAME} !-f
    RewriteRule ^ index.php [QSA,L]
</IfModule>

This will reroute every page to index.php when mod_rewrite module is active