Why the subbrute tool taking hours to find subdomain

[rishixpress]

I tried finding google.com subdomain to test, wheather my target domain has an error or tool is not working properly, the result is same because it takes too much time to even list 10-15 subdomains of google.com,it took 20-25 minutes to find these only.
My internet speed is good, machine is fast and working superb but this tool it not working as it should, I want to know, it's only me who's facing this problem or other people are also facing the same latency.

[DaddyBigFish]

yeah it's broken tool, no error control to skip quick enough