Automatic internal link

Paste code to function.php in Child theme

//Automatic internal link

add_filter( 'the_content', 'lv_auto_internal_links' );
add_filter( 'the_excerpt', 'lv_auto_internal_links' );
function lv_auto_internal_links( $text ) {
    $replace = array(
        'Xsolution' => '<a title="Xsolution - Giải pháp công nghệ" href="https://xsolution.vn">Xsolution</a>',
    );
    $text = str_replace( array_keys($replace), $replace, $text );
    return $text;
}

Demo