поиск по разделу через api CSearch::Search

CModule::IncludeModule('iblock'); 
 
$iblock_id = ...; 
$section_id = ...; 
$query = $_REQUEST['q'];
 
$items = CIBlockElement::GetList( 
  array(), 
  array( 
    'IBLOCK_ID' => $iblock_id,  
    'SECTION_ID' => $section_id,  
    'ACTIVE' => 'Y', 
    '%SEARCHABLE_CONTENT' => $query
  ), false, false, 
  array('ID', 'NAME', 'DETAIL_PAGE_URL') 
);