There are separate inventory pages for each of your asset types which you can see a list of by hovering over Asset Inventory in the top banner of your screen.
The exact parameters of your asset types may vary by setup but the generic Asset Inventory drop-down will be separated into Bridge & Culvert Network Master and OSS Network Master as well as a Setup option. Each Network Master option will take you to a Network Master window which lists all assets of that type.
Please view the Network Master window help page for additional information on the functionality available on those pages.