show empty message on empty taxonomy wordpress - php

Question

im working on wordpress theme and everything goes fine but i have this problem
i make a php page "taxonomy.php" it shows custom taxonomy posts
the problem i have if i visit empty taxonomy it shows me a posts from other taxonomy insted of showing error message
the code i use to display:
<?php
get_header();
$temp = $wp_query;
$wp_query = null;
$wp_query = new WP_Query();
$wp_query->query('showposts=9&post_type=covers'.'&paged='.$paged);
$term = $wp_query->queried_object;
?>
<div id="primary" class="site-content span12">
<div id="content" class="entry-content" role="main">
<?php
$product_terms = wp_get_object_terms($post->ID, 'cover_category');
if(!empty($product_terms)){
if(!is_wp_error( $product_terms )){
foreach($product_terms as $term){
echo '<h4 style="color:#cb2027">'.$term->name.'</h4>';
//Category Desciprion
echo '<h6 style="color:#cb2027">'.term_description($term->term_id, 'cover_category').'</h6>';
}
}
}
?>
<?php while ($wp_query->have_posts()) : $wp_query->the_post(); ?>
<h5><?php the_title(); ?></h5>
<?php endwhile; ?>
<?php get_footer(); ?>
Now if i visit this
http://localhost/wp/?cover_category=as -> this taxonomy as have 6 posts and show them correct
if i visit this http://localhost/wp/?cover_category=wawa -> this taxonomy wawa have 0 posts and it show posts from as taxonomy

Answer 1

This is an example for default category page:
<?php if ( have_posts() ) : ?>
<?php while ( have_posts() ) : the_post(); ?>
<div style="height: 190px;">
<?php if ( has_post_thumbnail()) : ?>
<div class="thumb" style="float: left; width:170px;">
<?php the_post_thumbnail('thumbnail'); ?>
</div>
<?php endif; ?>
<div style="float:left; width:475px;">
<h1><?php the_title(); ?></h1>
<?php the_excerpt(); ?>
En savoir plus
</div>
</div>
<?php endwhile; ?>
<?php else: ?>
<h3>Page en cours de construction</h3>
<?php endif; ?>