I usually recommend utilizing google based on the results comapred to the built in search engine of the docs site. So not just a google search but a search for "keyword1 keyword2... site:commvault.com" this usually let's me find the topics faster that directly on the site.
That said I'd also issue a word of warning when utilizing google search. While the results can be more direct to the content there's a lot of older version content that comes up in searches that may not be up to the latest information. That said there's some major differences in the documentation betwen versions that make it easier to use (e.g. V10 had a lot more screenshots, so when i send a link for someone they may prefer the more detailed documentation). Some info is very hard to find in newer versions that still can be found on the old documentation and this is where Google again shinest as we usually limit the search results on the docs.commvault.com site by selecting the applicaple version.
Hope that gave you some more feedback to your poll.