Imports System.Data.OleDb
Public Class Form1
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim connetionString As String
        Dim connection As OleDbConnection
        Dim oledbAdapter As OleDbDataAdapter
        Dim ds1 As New DataSet
        Dim ds2 As New DataSet
        Dim dt As DataTable
        Dim firstSql As String
        Dim secondSql As String
        Dim i As Integer
        connetionString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=Your mdb filename;"
        firstSql = "Your First SQL Statement Here"
        secondSql = "Your Second SQL Statement Here"
        connection = New OleDbConnection(connetionString)
        Try
            connection.Open()
            oledbAdapter = New OleDbDataAdapter(firstSql, connection)
            oledbAdapter.Fill(ds1, "First Table")
            oledbAdapter.SelectCommand.CommandText = secondSql
            oledbAdapter.Fill(ds2, "Second Table")
            oledbAdapter.Dispose()
            connection.Close()

            ds1.Tables(0).Merge(ds2.Tables(0))
            dt = ds1.Tables(0)

            For i = 0 To dt.Rows.Count - 1
                MsgBox(dt.Rows(i).Item(0) & "  --  " & dt.Rows(i).Item(1))
            Next

        Catch ex As Exception
            MsgBox("Can not open connection ! ")
        End Try
    End Sub
End Class