Hi!
is there an option in TOAD to display scheduler job run logs (from USER_SCHEDULER_JOB_RUN_DETAILS view) for a job which already finished it's execution and it is not displayed any more on scheduler job list (auto drop is set on true)?
Sorry, I don't think there is.
Thought so 
But I think this can be a nice feature to have in TOAD.
Do You know if there is any place on TOAD site on which proposals for new features can be posted?
You can do that here or in idea pond
But are you sure that there is still data for the deleted job in USER_SCHEDULER_JOB_RUN_DETAILS?
I have examples in my database where scheduler JOB was executed but failed, and because of "auto drop" attribute it was automatically dropped.
So it is not visible any more among scheduler jobs but it's run log stay available for some period of time... and it can be fetched from USER_SCHEDULER_JOB_RUN_DETAILS view. There You can find for example an error code and error backtrace, which is very important information to figure out what happened.