Hi Lolo, I really haven't gotten into studying this, I'm so sorry. But both parsley and dandelion root are dieuretic herbs.
The thing with the stones is you have to keep working at it, keep doing it daily, keep drinking parsley tea or taking capsules, drink lots of water. It won't happen overnight, but requires constant effort on your part.
Did you have a chance to do any research as well? I'm curious to know what you came up with too.