Carthik has a nice post on how to Search Ubuntu mailing list archive using 3rd party urls. According to him:
"Almost all of the tips I post here are either things I stumble upon myself or things that I read at the Ubuntu-users mailing list. Seeing as how useful this mailing list is, I thought there should be a fast, efficient way to search it. Mailman, the software that the list runs on does not provide good search functionality. Don't give up hope yet, though.
You can use Gmane's search functionality at http://news.gmane.org/gmane.linux.ubuntu.user."
Ubuntu mailing List is good. Generally, I prefer to use award wining Google search engine for searching any site or archives using Google site operator.
site: query modifiers
For example search cyberciti.biz for adding a user, you need to type search string:
site:cyberciti.biz add a user
Use same technique to search ubuntu mailing list archives using Google
site:lists.ubuntu.com add a user
Google will restrict the results to those websites in the given domain cyberciti.biz or lists.ubuntu.com with site: query modifiers.
intitle: query modifiers
For perfect accuracy just try to search any site title using intitle: query modifiers
intitle:linux add a user to group
You can also combine site: and intitle: query modifiers.
site:cyberciti.biz intitle:linux add a user to group
cahce: alternate query type and to highlight words
Sometime particular site goes down due to some problems, use cahce: operator to load same page to solve your problem. Cache is also good for highlighting words :)
cache:www.cyberciti.biz/faq/howto-linux-add-user-to-group/ add a user
PS: Use Google operators to search any information not just related to Linux/UNIX/BSD!