Send This Form Using SMTP And VB.NET?

My code was .... But it only send one field value to email .... I want multiple values to be send as it is in mail ... like ..

Category :
Your name :
Email ID
Mobile no. etc..

All form values will be transferred to mail ID ...

Imports System.Net.Mail
Protected Sub ImageButton1_Click(ByVal sender As Object, ByVal e As System.Web.UI.ImageClickEventArgs) Handles ImageButton1.Click
Try
Dim SmtpServer As New SmtpClient()
Dim mail As New MailMessage()
SmtpServer.Credentials = New Net.NetworkCredential("bus@volvobusesindia.com", "pink&777")
SmtpServer.Port = 25
SmtpServer.Host = "mail.volvobusesindia.com"
mail = New MailMessage()
mail.From = New MailAddress(TextBox12.Text)
mail.To.Add("bus@volvobusesindia.com")
mail.Subject = "New Bus Booking Query"
mail.Body = "Category :" & " " & DropDownList3.SelectedItem.Text
SmtpServer.Send(mail)
MsgBox("mail send")
Catch ex As Exception
MsgBox(ex.ToString)
End Try
End Sub