You can look up the lily's name in the Lily Register (link at top of lily forum). Use your pdf search function; you will have to search each pdf until you find it. You might try the gerrydanen link first for older lilies (up to around 2005 or so). It is quicker, just click on Search and type the name into the box that comes up. Dutch bred lilies are from Dutch companies that have dutch sounding names for the most part. World Breeding company is one exception that comes to mind.
Play around with it and see how it works for you. If you don't find the entry for the lily you are looking for it could be that it is not registered or it is too new to show up in the register.