Activate the asset command. For more information on how do so, see section 9.11.2.
Make sure the assets you wish to select are shown in the model. For more information on how to show assets in the model, see section 9.13.2.
Go to the model (see image below).
Select one or more assets by clicking one or more assets in the model. The asset or assets you select will be marked in red in the model and the graphical search field (see image below).