Tags query with regex

Hi,
Can anybody help me? I have many nodes by server names for example

systems.us-crons-system-prod-01_local
systems.us-crons-system-prod-02_local
systems.us-crons-system-prod-03_local
systems.us-redis-system-prod-01_local
systems.us-redis-system-prod-02_local

I try to use tags query:
aliasSub(systems.*,"^\w+-(\w+)-.*", "\1")
But it is not work.
What is wrong?