How to combine letters from different labels into one?

Question

gmail

I have, for example, 4 labels of different types Helpdesk, Test, Support and Monitoring. All of these 4 labels are under the "Tech. Support" level label. All messages are filtered so that they only go to these 4 labels of the level below. I would like when choosing Tech. Support to get all emails that contain Helpdesk, Test, Support and Monitoring labels.
This is what the staircase looks like:

Answer 1

To do this, it is enough to create a filter that includes the conditions of all four subtypes, and adds a top-level label.