You can list rooms matching a value you have selected. You can list from 2 to 250 rooms. If you do not specify the number of hits it will show you everything it finds up to the limit of 250.
/msg chanserv list *web*
/msg chanserv list *teen* 10
This can be useful if you need a particular type of room but aren't sure what it might be called. For example, you could try to find a help room about Windows by doing a search on *windows*, but this might miss #win95. A search done on *win* might turn up unrelated things like #winners. Another way to use this is to try to find rooms to be investigated for violating your network's rules. For example, you might not allow rooms about illegal file sharing, commonly called "warez". So you could do a search on *warez*, however, you should remember that if you try to find rooms this way, then people will start disguising their room names and making them look more innocent. The downside to that is that people may stumble into a room containing things they did not want to see.