a very serious call for help: the "richa movement"

Helloo, all

I have been practicing the oud for several years now, but unfortunately I live in a city and area where there is no Expert in Oud, so very often I have to travel to Paris to take oud lessons: the teachers are not always available, so I almost gave up last year.... But I am overwhelmed both by the music and the help some of you provide on this forum: I am now thriving to understand haw to strike the strings: there are many ways of doing it and I am a bit annoyed by the differences in what players say swiftly. What I really need is some explanations on how to move( rotate) ma right hand( axis or center of rotation). I am sure I will overcome the problem with you help, if anyone can post some drawings of the movement with details on the relative position of the movement and plane of the strings, etc...Many thanks, sandranis