Von coeverden/van coeverden/van covern

I have belonged for quite a while now and have never had anyone with the name I am searching for answer. I have traced my forebears back to Leer in 1773.
Georg Friedreich vanCoeverden(1773-Feb.6,1817) m. Grietje Lueloss/Lueloff (1776) in 1796. There are records of this name in the Netherlands, but there is no connection to this couple.. Neither are there any Germans further back than my GGGgrandfather named above. Would anyone be able to make a connection for me?
Thank you in advance for your help.
Ghyll (JILL) Simoneschi