There maybe cultural differences, but people are much the same.

At the begining of learning English When I first started to learn English, I was told that cultural differences are very important, and about/of that I have no doubt (in my mind)/I can't deny that. So many countries in our world, so many (different) people (there): (the) rigorous/strict Germans, passionate Americans, polite Japanese and hard-working Chinese, etc. -- we've always had different stereotypes to about/of people from other locations/places. Yes, people from different countries are different -- that's right and I couldn't agree any more. But after years of learning languages, I realize that everyone is alike.

Men love to talk about women and sex, and/while women enjoy talking about make up.
It's simply a metaphor a simple stereotype but it's true. Just It is because of the our educations, environments, and backgrounds that our world is so colourful and vigorous vibrant/lively.

Everybody thinks that they are/he is the best, that nobody around him can beat him. They have/He has [Make sure pronouns agree!] talents but just nobody can find out nobody knows about them, (and) that's why he looks so ordinary to people around him.
Everybody wants a comfortable and wealthy life, maybe not rich, but carefree. No need to walk with the boring clients while working/No need to work with boring clients, they can quit their job (at) any time they want if they don't like it, they can even to buy anything they like without too much considerations of bills coming next week/without thinking too much about next week's bills.
Kids want to be a superheroes, girls dream about their Mr. Right, the olds elderly love children and to travel. People in of their different ages have various, but the same demands/have various demands, but they are the same. We always want to distinguish us ourselves from others, but in fact the rest of us are doing the same thing.

Chinese people regard foreigners as a well-educated group; those who is are able to come to China should be very rich, polite or smart. Not/It isn't until we one day the day we find meet/come across a foreigner who ran a red light, just like us, did do we realize they are same like as us, influenced by the our environment. Chinese people stay in the long queues insteady of jumping the queue when they travel overseas, as because they find out/learn that everybody is following the rules (I know still few can not follow/I know a few still cannot follow them).

As a result, I agree with the cultural diversification, but people are all the same, share one world and have/lead a normal lives.