public ResponseModel TimKiem(string keyword, string shopName, int?maloai, string maloai1, string maloai2,
int?min, int?max, int?pageIndex, int?pageSize, bool?lowToHighPrice, bool?newestFirst)
{
min = min ?? 0;
var response = new ResponseModel();
long total = 0;
response.NullableIndex = pageIndex;
response.NullableSize = pageSize;
response.Data = isp.TimKiemSanPham(keyword, min, max, shopName, pageIndex, pageSize, maloai, maloai1, maloai2, lowToHighPrice, newestFirst, out total);
response.TotalItems = total;
return(response);
}