Dùng Fulltext search kết hợp với tìm kiếm truyền thống phần 3 (ok)

function wpdocs_save_meta_box( $post_id, $post, $update  ) { 
    $categories = [];
    $sting = $sting2 = "";
  $categorie1 = get_the_terms($post_id, 'area_category') ? get_the_terms($post_id, 'area_category') : [];
  $categorie2 = get_the_terms($post_id, 'welfare_category') ? get_the_terms($post_id, 'welfare_category') : [];
  $categorie3 = get_the_terms($post_id, 'job_category') ? get_the_terms($post_id, 'job_category') : [];
  $categorie4 = get_the_terms($post_id, 'recruitment_category') ? get_the_terms($post_id, 'recruitment_category') : [];
  $categories = array_merge($categorie1,$categorie2,$categorie3,$categorie4);
  $p3_re            = get_post_meta($post_id,'p3_re');
  $p6_re_0_p6_title             = get_post_meta($post_id,'p6_re_0_p6_title');
  $p6_re_0_p6_content           = get_post_meta($post_id,'p6_re_0_p6_content');
  $p4_t1            = get_post_meta($post_id,'p4_t1');
  $p4_t2            = get_post_meta($post_id,'p4_t2');
  $p4_t3            = get_post_meta($post_id,'p4_t3');
  $categories2 = array_merge($p3_re,$p6_re_0_p6_title,$p6_re_0_p6_content,$p4_t1,$p4_t2,$p4_t3);
  if(!empty($categories2)) {
    foreach ($categories2 as $key => $categorie2) {
        $sting2 .= " " .trim($categorie2). " ";
    }
  }
  $sting2 =  trim(preg_replace("/\s\s+/", " ", $sting2));
  if(!empty($categories)) {
    foreach ($categories as $key => $categorie) {
        $sting .= " " .trim($categorie->name). " ";
    }
  }
  $sting = trim($sting);
  if($sting2) {
    $sting = $sting . " " . $sting2;
  }
  if( $sting ) :  
   update_post_meta($post_id, 'set_post_category_taxonomy', $sting); 
   estar_child_move_data_company($post_id,$sting);
  endif; 
}
add_action( 'save_post', 'wpdocs_save_meta_box',10,3 );
function estar_child_move_data_company( $post_id ,$sting) {
    global $wpdb;
    $data = [];
    $data['ID'] = $post_id;
    $data['set_post_category_taxonomy_custom'] = get_post_meta( $post_id, 'set_post_category_taxonomy', true );
    $data = array_filter( $data );
    $reset = $wpdb->query( $wpdb->prepare( " SELECT * FROM wp_post_category_taxonomy WHERE ID = $post_id ") );
    if ( $data && $reset ) {
        $wpdb->query( $wpdb->prepare( " UPDATE wp_post_category_taxonomy SET set_post_category_taxonomy_custom = '$sting' WHERE wp_post_category_taxonomy.ID = $post_id ") );
    }else {
        $wpdb->insert( 'wp_post_category_taxonomy', $data );
    }
}
// ??
$use_custom_search = !empty($_GET['s']);
if ($use_custom_search) {
    function __adapted_search_function($search, $query) {
      if (is_admin() || !$query->is_main_query() || !$query->is_search) {
        return;
      }
      global $wpdb;
      $search_term = $query->get('s');
      $search      = " ";
      add_filter("posts_join", '__custom_join_tables');
      add_filter('posts_where', 'posts_where');
      add_filter('posts_fields', 'custom_posts_fields');
      add_filter( 'posts_groupby', 'my_posts_groupby' );
    add_filter('posts_orderby', 'orderby_pages_callback', 10, 2);
      return $search;
    }
    function posts_where($where) {
      global $wpdb;
      $keywords = get_query_var('s');
      $newout = $keywords;                       // 「残業　福岡」
      $newout = $test = "";
      $newout .= preg_replace('/\s+/', ' ', $keywords); 
      $newout = trim($newout);
      $leng = explode(' ', $newout);
      $lengs = $lengs2 = array();
      foreach($leng as $le) {
        $lengs[] ="%{$le}%";
      }
      foreach($leng as $le) {
        $lengs2[] ="{$le}";
      }
      $newout2 = implode(" ",$lengs2);
      foreach ($lengs as $value) {
        $test .= " OR wp_post_category_taxonomy.set_post_category_taxonomy_custom LIKE '{$value}' "; 
      }
      $where = " AND {$wpdb->posts}.post_status = 'publish' AND {$wpdb->posts}.post_type = 'post' AND ((MATCH({$wpdb->posts}.post_title) AGAINST ('$newout2' IN BOOLEAN MODE) AND {$wpdb->posts}.post_status = 'publish') OR (MATCH(wpma.meta_value) AGAINST ('{$newout2}' IN BOOLEAN MODE) AND {$wpdb->posts}.post_status = 'publish')) ";
      $where .= $test; 
      return $where;
    }
    function __custom_join_tables($joins) {
      global $wpdb;
      $joins .= " LEFT JOIN $wpdb->postmeta AS wpma ON (wpma.post_id = {$wpdb->posts}.ID) LEFT JOIN wp_post_category_taxonomy ON (wp_post_category_taxonomy.ID = {$wpdb->posts}.ID) ";
      return $joins;
    }
    function custom_posts_fields($fields) {
      global $wpdb;
      $fields = " * ";
      return $fields;
    }
    function my_posts_groupby($groupby) {
      global $wpdb;
      $groupby = " {$wpdb->posts}.ID ";
      return $groupby;
    }
    function orderby_pages_callback($orderby_statement, $wp_query) {
        global $wpdb;
    # Verify correct post type, or any other query variable
    if ($wp_query->get("post_type") == "post") {
        # In this trivial example add a reverse menu order sort
        return " {$wpdb->posts}.post_date DESC ";
    } else {
        # Use provided statement instead 
        return $orderby_statement;
    }
    }
    add_action('posts_search', '__adapted_search_function', 1, 2);
}
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