you would do something like the code below to create the filter functionality. Also take a look at this example: http://allenbrowne.com/ser-62.html
Code:
Dim criteria As String
'check to see if the name combo box has a selection
If Not IsNull(Me.YourComboBoxNameHere) Then
criteria = "[NAME_FieldNameHere] = """ & Me.YourComboBoxNameHere & """ AND "
End If
'check to see if there is a date selected
If Not IsNull(Me.YourDateControlHere) Then
criteria = criteria & "[DATE_FieldNameHere] = #" & Me.YourDateControlHere & "# AND "
End If
'if the user made at least one selection then apply the filter
If criteria <> "" Then
'remove the trailing " AND "
criteria = Left(criteria, Len(criteria) - 5)
'apply the filter
Me.Filter = criteria
Me.FilterOn = True
Else
'remove the filter
Me.Filter = ""
Me.FilterOn = False
End If