YouTube doesn't focus much on Geography when it comes to discovery. Think about it; when you do a search on YouTube how often do you get results catered to you by geographic location?
The results that you are getting are the direct result of your audience. A certain audience is responding to your content and so it is similar audiences that YouTube is sharing you out to. You can expand this by translating your captions, titles and descriptions into different languages, but be aware that there are likely cultural things that you may not even know you are doing (a thick accent, filming style etc) which are impacting your audience and causing these results.