With the ZuluPeople there is 3 different healers.

Nyanga-Docter
Sangoma-Traditional Docter
Nganga-Witchdocter

Last year year or the year before there was a south-African movie launched all over the world.It is a comedy with local and american actors.It is a comedy but it will give you an idea of a sangoma/nganga.
The name of the movie is Mr.Bones.
See if can get hold of it.Any person who likes africa will enjoy this movie.