it seems to me that we know more about the history of civilizations and countries in the Western hemisphere than countries and civilizations like Africa, China and India.

Is the explanation a trivial case of - we live in the Western world, and historians tend to focus on that?

I am slightly confused by your question. Who are you referring to when you say "we"? Are you talking about redditors and history buffs?

Are you asking about pop culture and/or popular media treatments of history?

Or are you talking about "what we know" in the sense of academia and the sum of human knowledge?

Each of those questions will lead to different answers.

You know this is such a simple answer, but maybe if you are not multicultural like me, who speaks 4 different languages, and is Chinese and Canadian at the same time, you may not realize it. Though the same can be said of the Chinese and Indians.

Chinese history is written in Chinese, and Indian in Indian. Though even without going that far to the east, consider German, the Franco Prussian war and the Austro Prussian war are glossed over, while insignificant events like the Scottish English wars under Edward Longshanks are talked about again and again.

We each focus on the history we made. Another example is Japan, Japanese writing came from China, and yet, in the Western hemisphere, more know of Sengoku Jidai, then the Waring States period in China, which took place more than a thousand years prior to that.

Perspective is everything.