Discover searches across most of the library databases including Academic Source Ultimate, so you will easily find journal articles from ASU by searching Discover.
But if you would like to search more specifically for contents in ASU, it will be for efficient for your to go directly to ASU database itself, since in Discover it is sometimes difficult and tricky to identify contents from ASU in the Discover result list.
Check the following FAQ to see the differences between Discover and library databases.
