I recently wanted to search shops in a small French city while being in Finland. Unfortunately the name of the city happened to be very close to a rather common Finnish word (not even really identical). Google insisted to show me Finnish hits, I could not find a way by quoting and adding semi-common French search words to make their algorithms what I want. I could just not get up any reasonable French matches.
Just to demonstrate the effect to myself I took a VPN connnection to France and voilà, very useful hits.
That's the geographic dimension of the search bubble. I am sure there are more.
(I never use Google search when I am logged in to Google and I delete my cookies at least daily. So things should be pretty neutral for me. Someone might say, hah, your fault. If you hadn't subverted their profiling you'd get better results. I doubt that, I had not heard about that French city before and I certainly search more Finnish pages than French ones.)