Как вывести текст в похожих новостях, если он относится к определенный категории?

                    $related['category'] = intval( $related['category'] );

                    $category_id = $related['category'];

                    if( strpos( $tpl2->copy_template, "[catlist=" ) !== false ) {
                        $tpl2->copy_template = preg_replace_callback ( "#\\[(catlist)=(.+?)\\](.*?)\\[/catlist\\]#is", "check_category", $tpl2->copy_template );
                    }

                    if( strpos( $tpl2->copy_template, "[not-catlist=" ) !== false ) {
                        $tpl2->copy_template = preg_replace_callback ( "#\\[(not-catlist)=(.+?)\\](.*?)\\[/not-catlist\\]#is", "check_category", $tpl2->copy_template );
                    }

while ( $related = $db->get_row() ) {

        if( strpos( $tpl2->copy_template, "[catlist=" ) !== false ) {
            $tpl2->copy_template = preg_replace_callback ( "#\\[(catlist)=(.+?)\\](.*?)\\[/catlist\\]#is", "check_category", $tpl2->copy_template );
        }
                                
        if( strpos( $tpl2->copy_template, "[not-catlist=" ) !== false ) {
            $tpl2->copy_template = preg_replace_callback ( "#\\[(not-catlist)=(.+?)\\](.*?)\\[/not-catlist\\]#is", "check_category", $tpl2->copy_template );
        }