How to connect quickbooks using C# return data in Arabic language

i found this code and can make connection with Quickbooks but the items name and description  is in Arabic it get back like this ?????????
i need help to convert it to get data from quickbooks in arabic 

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using Interop.QBFC14;

QBSessionManager _MySessionManager = new QBSessionManager();
           _MySessionManager.OpenConnection2("", "Your App Name", ENConnectionType.ctLocalQBDLaunchUI);
         //  _MySessionManager.OpenConnection2("", "Your App Name", ENConnectionType.ctLocalQBD);
           _MySessionManager.BeginSession("", ENOpenMode.omDontCare);
           var version = QBFCLatestVersion(_MySessionManager);
           short ver = Convert.ToInt16(version);

            IMsgSetRequest itemRequestset = _MySessionManager.CreateMsgSetRequest("US", 13, 0);
           IItemQuery itemQuery = itemRequestset.AppendItemQueryRq();
           itemQuery.OwnerIDList.Add("0");
           IMsgSetResponse responseItemRq = _MySessionManager.DoRequests(itemRequestset);
           IResponseList itemResponseList = responseItemRq.ResponseList;

             IResponse itemResponse = itemResponseList.GetAt(0);

           ENResponseType responseType = (ENResponseType)itemResponse.Type.GetValue();
           IORItemRetList QBItemList = (IORItemRetList)itemResponse.Detail;
           for (int i = 0; i <= QBItemList.Count - 1; i++)
           {
               if (QBItemList.GetAt(i).ItemNonInventoryRet != null)
               {
                   IItemNonInventoryRet inventoryItem = QBItemList.GetAt(i).ItemNonInventoryRet;
                   string ListID = inventoryItem.ListID != null ? inventoryItem.ListID.GetValue() : "";
                   string ItemCode = inventoryItem.Name != null ? inventoryItem.Name.GetValue() : "";
                  // string Description = inventoryItem.FullName.GetValue() != null ? inventoryItem.FullName.GetValue() : "";
                   string Description = inventoryItem.FullName.GetValue();
                   Description= Utf16ToUtf8(Description);
                   string MPN = inventoryItem.ManufacturerPartNumber != null ? inventoryItem.ManufacturerPartNumber.GetValue() : "";
                   rt1.AppendText(ItemCode.ToString() + Environment.NewLine);
                   rt1.AppendText(Description.ToString() + Environment.NewLine);

               }
               else if (QBItemList.GetAt(i).ItemInventoryRet != null)
               {
                   IItemInventoryRet inventoryItem = QBItemList.GetAt(i).ItemInventoryRet;
                   string ListID = inventoryItem.ListID != null ? inventoryItem.ListID.GetValue() : "";
                   string ItemCode = inventoryItem.Name != null ? inventoryItem.Name.GetValue() : "";
                   // string Description = inventoryItem.SalesDesc != null ? inventoryItem.SalesDesc.GetValue() : "";
                   string Description = inventoryItem.SalesDesc.GetValue().ToString().ToUTF8();
                   string MPN = inventoryItem.ManufacturerPartNumber != null ? inventoryItem.ManufacturerPartNumber.GetValue() : "";
                   //  string Price = inventoryItem.SalesPrice.GetValue();
                   Description = Utf16ToUtf8(Description);
                   rt1.AppendText(ItemCode.ToString() + Environment.NewLine);

                   rt1.AppendText(Description.ToString() + Environment.NewLine);
               }
               else if (QBItemList.GetAt(i).ItemInventoryAssemblyRet != null)
               {
                   IItemInventoryAssemblyRet inventoryItem = QBItemList.GetAt(i).ItemInventoryAssemblyRet;
                  // customFieldsList = string ListID = inventoryItem.ListID != null ? inventoryItem.ListID.GetValue() : "";
                   string ItemCode = inventoryItem.Name != null ? inventoryItem.Name.GetValue() : "";
                   string Description = inventoryItem.SalesDesc.GetValue() != null ? inventoryItem.SalesDesc.GetValue() : "";
                   string MPN = inventoryItem.ManufacturerPartNumber != null ? inventoryItem.ManufacturerPartNumber.GetValue() : "";

                   rt1.AppendText(ItemCode.ToString() + Environment.NewLine);

                   rt1.AppendText(Description.ToString() + Environment.NewLine);
               }
               else if (QBItemList.GetAt(i).ItemServiceRet != null)
               {
                   IItemServiceRet inventoryItem = QBItemList.GetAt(i).ItemServiceRet;
                   // customFieldsList = string ListID = inventoryItem.ListID != null ? inventoryItem.ListID.GetValue() : "";
                   string ItemCode = inventoryItem.Name != null ? inventoryItem.Name.GetValue() : "";
                   Console.WriteLine(ItemCode);
                   Console.WriteLine(ItemCode);
                   rt1.AppendText(ItemCode.ToString() + Environment.NewLine);
                 //  rt1.AppendText(Description.ToString().ToUTF8() + Environment.NewLine);


               }

can any one help me please