A lot of STC's have their own output spool datasets. You might find what you are looking for by investigating the executing STC under SDSF.
i m already executing the STC under SDSF
but i can only view the JES2 messages when logging with the job owner "ibmuser"
i need to know how to display the JES2 messages of STC for users other than ibmuser
check the RACF definition to find out the default "USER" and/or the default "GROUP" for started tasks, or have the SDSF/security administrator grant You the adequate authority to browse the STC sysouts.