Android Question bluetooth print not work

If Success Then
' printer.Initialize2(mz320.OutputStream,"tis620")
printer.Initialize2(mz320.OutputStream,"utf8")
printer.Write(tprint.Text)

printer.Flush


Msgbox("Printed!","")
printer.Close
mz320.Disconnect
Else
If Msgbox2("", "Printer Error","Reprint","Cancel","",Null) = DialogResponse.POSITIVE Then
StartPrinter
End If
End If


printer Zebra MZ320
how i can resolve this problem
i want to print out with Thai language