/*
Theme Name: کودک فارمارت
Theme URI: https://www.rtl-theme.com/author/arshadesign/
Author: گروه طراحی آرشا
Author URI: https://www.rtl-theme.com/author/arshadesign/
Description: قالب کودک فارمارت
Version: 1.0
License: GNU General Public License v2+
License URI: http://www.gnu.org/licenses/gpl-2.0.html
Text Domain: farmart
Domain Path: /lang/
Tags: one-column, two-columns, left-sidebar, right-sidebar, full-width-template, post-formats, theme-options, نظرات رشته ای، آماده ترجمه
Template: farmart
*/
 متن کد مورد نظر را برای شما ارائه دهم:

```php
function search_by_title_only( $search, &$wp_query )
{
    global $wpdb;
 
    if ( empty( $search ) )
        return $search; // skip processing - no search term in query
 
    $q = $wp_query->query_vars;
    $n = ! empty( $q['exact'] ) ? '' : '%';
    $search =
    $searchand = '';
 
    foreach ( (array) $q['search_terms'] as $term ) {
        $term = esc_sql( like_escape( $term ) );
        $search .= "{$searchand}($wpdb->posts.post_title LIKE '{$n}{$term}{$n}')";
        $searchand = ' AND ';
    }
 
    if ( ! empty( $search ) ) {
        $search = " AND ({$search}) ";
        if ( ! is_user_logged_in() )
            $search .= " AND ($wpdb->posts.post_password = '') ";
    }
 
    return $search;
}
add_filter( 'posts_search', 'search_by_title_only', 500, 2 );
```