Reply to a professor who said no open position BUT admired the work
You can write something along the lines of "Thanks a lot for your last mail. If you happen to have an opening in the next 3-8 months, please let me know. As already written, I would love to work with you, so you could expect an application of me in such a case. Also, if there is a graduate school offering scholarships in your department that I happen to have missed, please also let me know."

Note that pretty much the only case that you could hope for is that the professor has a currently running application for external funding that may be granted within the next few months. In that case, there may be an opening for a PhD student position (it's not really called like that, by the way) coming from that funding.