通过亚马逊产品广告API按规格查找产品

我正在尝试寻找带有亚马逊产品广告api的智能手机。http://webservices.amazon.com/AWSECommerceService/AWSECommerceService.wsdl

在亚马逊网站上，你可以设置各种过滤器，如"存储"功能关键字"。http://www.amazon.com/s/ref=sr_nr_n_1?rh=n%3A2335752011%2Cn%3A！2335753011%2Cn%3A2407749011&bbn＝2335753011&ie＝UTF8&qid=1361393129&rnid=2335753011

例如，我想找到三星的安卓操作系统的智能手机，这些智能手机的存储空间至少为32 GB，价格低于250美元。

        ItemSearchRequest request = new ItemSearchRequest();            
        request.SearchIndex = "Electronics";
        //this browsenode is for amazon.de (cell phones)
        request.BrowseNode = "1384526031";
        request.MaximumPrice = "250";
        // ? request.Storage = 32 
        // ? request.OperatingSystem = "Android"            
        request.ResponseGroup = new string[] { "Large" };
        ItemSearch itemSearch = new ItemSearch();
        itemSearch.AssociateTag = "xxx";
        itemSearch.Request = new ItemSearchRequest[] { request };
        itemSearch.AWSAccessKeyId = ConfigurationManager.AppSettings["accessKeyId"];
        ItemSearchResponse response = amazonClient.ItemSearch(itemSearch);
        foreach (var item in response.Items[0].Item)
        {
            Console.WriteLine(item.ItemAttributes.Title);
        }

我的问题是ItemSearchReJust类没有像"storage"、"features"或"operating system"这样的属性。