Usually Google restricts its results to the language you have set for the page itself, which is the one spoken in the country it locates you in by default. You can easily change these settings by clicking on the cog
Add language packs on Windows 8
Before Windows 8, language packs other than the one your Windows shipped with were reserved for users of the more expensive versions. This however will change in future as one can read on the msdn blog and see on the