OleDbDataAdapter1.SelectCommand.CommandText = "SELECT * FROM Immo WHERE (Lift" & _
  "Like " & ConvertBooleanToSQLString(CheckBox1.Checked) & " AND EBK Like " & _
  ConvertBooleanToSQLString(CheckBox2.Checked) & " And VArt LIKE '" & _
  ComboBox1.Text & "%' And Heizung Like '" & ComboBox4.Text & "%' And Objektart" & _
  "Like '" & ComboBox2.Text & "%' And Zustand Like '" & ComboBox3.Text & "%'" & _
  "And Baujahr Like '" & TextBox1.Text & "%' And Etage Like '" & TextBox2.Text _
  & "%' And Einheiten Like '" & TextBox3.Text & "%' And Zimmer Like '" & _
  TextBox11.Text & "%')"
        DataSet31.Clear()
        OleDbDataAdapter1.Fill(DataSet31)
 
Private Function ConvertBooleanToSQLString(Value as Boolean) as String
    if Value then
        Return "TRUE"
    else
        Return "FALSE"
    end if
End Function