Two issues identified:

1.  Query returns anchors that have one ore more requested modules instead of those that have ALL requested modules. 
2. no result handling:
   1. If existing module-names are given but there is no cm-handle has all of them the system returns 500 Status Code. Should return 200 Status with empty collection instead
   2. Only when non-existing module-names are supplied an 500 Error might be returned details which Module-name(s) do not exist at all.