Private Sub partnerCity_LostFocus()
  filtersLostFocus
End Sub

Private Sub filtersLostFocus()

  Dim str As String

  ' еще немного фильтров...
  
  If Not (IsNull(partnerCity.value) Or IsEmpty(partnerCity.value) Or partnerCity.value = "") Then
    str = str + ", @cityID = N'" + DoubleQuote(partnerCity.value) + "'"
  End If
  
  str = cDataSource + Mid(str, 2)
  
  If (Me.RecordSource <> str) Then
    Me.RecordSource = str
  End If

End Sub