Menggunakan kerangka thinkphp

$search=urldecode(I("search"));
        $this->assign('search',$search);
        if(!empty($_POST)){
        
            //$condition = array();
            $condition['goods_name']=array("like","%$search%");
            //I('brand') ? $condition['brand_id'] = I('brand') : false;
            if(I('brand')){
                $condition['brand_id']=
            }
            //$condition['brand_id'] =80;
            //I('func') ? $condition['func'] = I('func') : false;
            //I('price') ? $condition['shop_price'] = I('price') : false;

            var_dump($condition);

            //$gList = M('Goods')->where($condition)->select();
           
            //echo "<pre>";
            //var_dump($gList);
            //echo "</pre>";
            
            
        }

Saya menulisnya seperti ini, tetapi ia tidak boleh menjadi pertanyaan berbilang pilihan dengan berbilang syarat. Sila beritahu saya cara menulis sql