In your map, you can create a drawing layer in Display Manager that includes all the objects in an object class in the current drawing.
To bring in drawing objects based on object classes in the current drawing
AutoCAD Map 3D creates a layer in Display Manager for each object class you select.
If you combine the layers in a group, you can turn the display of the group on or off.
The new layer appears in Display Manager. All objects in the selected object class are included in this layer. If you selected multiple object classes, multiple layers are created. To see the objects, you may need to zoom to the drawing extents.