Question: How to see a vacancies list of all published medias?
Answer: It’s not possible to combine medias in the one and same vacancies list. The solution would be to make sure to publish all ads always to a media (e.g. Homepage), or to create a media (e.g. All) where users make sure to publish to this media regardless whenever publishing an ad.
Question: How to exclude vacancies published on sub departments?
Answer: It's not possible to exclude any vacancies published to a media. If you would not want vacancies from a sub department to be shown then you would have to make sure to use separate medias for those vacancies that should not be shown together.