question to svchost

Hi!

I've got a question about services that are grouped together in a svchost-process. How does Windows controls which services run in the same svchost? Which informationen has to be equal or general to be set?

I tried to solve it with sc.exe and the HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\SvcHost-key, but I was not able to control the services...

Thanks in advance!

Greetings, Malte
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