Hi @Toshiaki_Takano,
In case you are using Rhino 6 / Windows version, try this script. It will select all layers of the selected objects and expand the layer stack as-needed. There is also an option to go back to original layer panel state in case you want to just quickly look and not mess things up by expanding the entire structure.
It can be put into button or macro, if needed, so it can be one quick key-press away… The Layer selection tools have been added to Rhino 6 RhinoScript, so it was not possible to make it work before. Hope that helps.
SelectObjectsLayers.rvb (1.7 KB)
–jarek