Search between two dates w/ datarows in vb 2010 - vb.net

Question

I am trying to search between two dates in a bound source (SQL table) in VB 2010, using data rows. Since 'between' in unsupported with the data rows function, I used < and >.
So I run this code and the output is 900+ entries when the actual number of entries is 8. After hitting my button a second time without changing anything, the correct number of entries appears.
Private Sub cmdSearch_Click(sender As System.Object, e As System.EventArgs) _
Handles cmdSearch.Click
Dim Expression As String
Dim OrderStr As String = "Area"
Dim DateStr As String
Dim StartDate As String
Dim EndDate As String
Dim Shift As String = ""
Dim Area As String = ""
Dim Product As String
If (DtpStartDate.Value = Nothing Or DtpEndDate.Value = Nothing) Then
MsgBox("Please input a start and end date.")
Exit Sub
End If
If (radShiftAllSearch.Checked <> True _
And radShiftOneSearch.Checked <> True
And radShiftTwoSearch.Checked <> True _
And radShiftThreeSearch.Checked <> True) Then
MsgBox("Please select a shift to search for.")
Exit Sub
End If
Select Case True
Case radShiftOneSearch.Checked
Shift = " AND [Shift] = '1'"
Case radShiftTwoSearch.Checked
Shift = " AND [Shift] = '2'"
Case radShiftThreeSearch.Checked
Shift = " AND [Shift] = '3'"
Case radShiftAllSearch.Checked
Shift = " AND ([Shift] = '1' OR [Shift] = '2' OR [Shift] = '3')"
End Select
**StartDate = DtpStartDate.Value.Subtract(oneday)
EndDate = DtpEndDate.Value.Add(oneday)
'StartDate = Format(DtpStartDate.Value.Subtract(oneday), "M/dd/yyyy")
'EndDate = Format(DtpEndDate.Value.Add(oneday), "M/dd/yyyy")
DateStr = "[Dates] > '" & StartDate & "' AND [Dates] < '" & EndDate & "'"**
If (txtProductSearch.Text = "") Then
Product = ""
Else
Product = "AND [Product] LIKE '" & txtProductSearch.Text & "'"
End If
For h As Integer = 0 To CheckedListBox1.CheckedItems.Count - 1
Dim XDRV As DataRowView = CType(CheckedListBox1.CheckedItems(h), DataRowView)
Dim XDR As DataRow = XDRV.Row
Dim XDisplayMember As String = XDR(CheckedListBox1.DisplayMember).ToString()
If (Area = "") Then
Area = Area & " AND ([Area] LIKE '" & XDisplayMember & "'"
Else
Area = Area & " OR [Area] LIKE '" & XDisplayMember & "'"
End If
Next
If (Area <> "") Then
Area = Area & ")"
End If
Expression = DateStr & Product & Shift & Area
TextBox4.Text = Expression
Dim SearchRows() As DataRow = _
ProductionDataSet.Tables("Production_Daily").Select(Expression, OrderStr)
'foundcount = SearchRows.Count - 1
DataGridView1.DataSource = SearchRows
DataGridView1.Show()
End Sub
Thanks