I only get one result

Hello, I am creating a template and implementing a search based on the Relevansi plugin using Live Ajax Search, but have encountered a problem. For some reason only one record is displayed in the results.
Here is my PHP for the search:

add_action('wp_ajax_nopriv_ajax_search', 'my_ajax_search');
add_action('wp_ajax_ajax_search', 'my_ajax_search');

function my_ajax_search() {
    global $wpdb;
    if (function_exists('relevanssi_do_query')) {
        $search_term = sanitize_text_field($_POST['search']);
        
        
        $search_query = new WP_Query();
        $search_query->query_vars['s'] = $search_term;
        $search_query->query_vars['posts_per_page'] = 5;
        relevanssi_do_query($search_query);

        if ($search_query->have_posts()) {
            echo '<strong>' . count($search_query) . '</strong>';
            while ($search_query->have_posts()) {
                $search_query->the_post();
                
                load_template(get_template_directory() . '/template-parts/ajax-search-result-item.php');
            }
        } else {
            echo 'Nothing.';
        } 
    }
    wp_die(); 
}

Here is my JS for the search:

function fetchSearchResults(searchValue) {
        var xhr = new XMLHttpRequest();
        xhr.open('POST', '/wp-admin/admin-ajax.php', true);
        xhr.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
        xhr.onload = function() {
            if (this.status === 200) {
                searchResults.innerHTML = this.responseText;
                handleSearchResults(); 
            } else {
                searchResults.innerHTML = '<p>Search ERROR</p>';
                showPopularQueries(); 
            }
        };
        xhr.onerror = function() {
            searchResults.innerHTML = '<p>Search ERROR</p>';
            showPopularQueries();
        };
        xhr.send('action=ajax_search&search=' + encodeURIComponent(searchValue));
    }