Wordpress通过儿童主题“阅读更多”而不是博客主页上的完整帖子

This is the blog: http://radutanasescu.ro/

This is the theme: https://wordpress.org/themes/responsive/

The child theme: http://cyberchimps.com/guide/child-theme-example/

And looking here: https://codex.wordpress.org/Customizing_the_Read_More, I tried to convince the theme to show excerpts instead of full posts on the Homepage by typing this in the child themes function.php file like this:

<?php 
    function new_excerpt_more($more) {
        //die('no yolo :(');
        global $post;
        return '<a class="moretag" href="'. get_permalink($post->ID) . '"> Read the full article...</a>';
    }
    function child_theme_setup() {
        //die('yolo works');
        // Replaces the excerpt "more" text by a link
        add_filter('excerpt_more', 'new_excerpt_more');
    }
    add_action( 'after_setup_theme', 'child_theme_setup' );
?>

It's obviously not working because I'm a php noob, if un-commented die('yolo works'); works and die('no yolo :('); doesn't.