Thanks for the reply.

I was actually looking to exclude certain categories from the Full Blog element of visual composer. I have 20 categories of posts, but I only want 19 to display.

I figured out how to this in code, however. I ported over /specular/vc_templates/home_blog.php to my child theme and then edited this line:

      if($dynamic_from_where == 'all_cat')
          query_posts('posts_per_page='.(int)$posts_per_page.'&paged='.get_query_var( 'paged' ) ); 
        else
          query_posts('posts_per_page='.(int)$posts_per_page.'&cat='.$dynamic_cat.'&paged='.get_query_var( 'paged' ) );
        

And you change it to this:

      if($dynamic_from_where == 'all_cat')
          query_posts( array( 'posts_per_page='.(int)$posts_per_page.'&paged='.get_query_var( 'paged' ), 'cat'=>'-244' ) ); 
        else
          query_posts('posts_per_page='.(int)$posts_per_page.'&cat='.$dynamic_cat.'&paged='.get_query_var( 'paged' ) );
        

‘244’ is the category ID of the category you’re looking to exclude.