put it wp root folder reach it by the browser once to remove all visual composer tag from your db

clean_visualcomposer_tag_from_post_content

<?php
// put it wp root folder reach it by the browser once to remove all visual composer tag from your db
// 
echo'<pre>';
// Include the wp-load'er
include('wp-load.php');

$query = new WP_Query( array(  'posts_per_page' => '-1' ) );
while ($query->have_posts()) : $query->the_post();
	
//print_R( $post->post_title );
	$my_post = array(
      'ID'           => $post->ID,
      'post_content' => preg_replace("/(\[(\/?)vc.*?\])/s", '', $post->post_content)
  );
// Update the post into the database
  wp_update_post( $my_post );
	echo '<br>';
  echo 'update product ID '.$post->ID;
endwhile;