Dim Search As String = "Vova" 
        Dim cmd As New OleDbCommand("", conn)

        If Search <> String.Empty Then
            conn.Open()
          cmd.CommandText = "SELECT LastName, BirthDate FROM Pensioner WHERE [FirstName]  ='" & Search & "'"

            Dim reader As OleDb.OleDbDataReader = cmd.ExecuteReader()

            If reader.HasRows Then  
                TextBox3.Text = (Search) 
            Else
                MsgBox("Такого пользователя нет!")
           End If
            reader.Close()
            conn.Close()
        Else
            MsgBox("Заполните поле")
        End If
    End Sub

TextBox2.Text = reader("LastName") 

TextBox2.Text = reader.GetString(0) 

TextBox2.Text = reader.Item(0) 

TextBox2.Text = reader(0).ToString() 

TextBox2.Text = reader.GetValue(0)