Chinese undergraduates, what's wrong with your social communication skills?

Several years ago, I had an experience living with three Chinese undergraduates. When I moved in my new room, on the first day, I knocked their doors and said hello to them. They seemed introvert and a bit rude. However, considering their age, I found it normal. After all, it was their first time abroad.

During the following months, I proactively went to chat with them and the situation began to change. I found they were not introvert anymore. On the contrary, when we talked about anything interesting, they always engaged in conversation more actively than before. I thought I had successfully rebuilt myself as an approachable person in front of them by putting extra efforts. In addition, I found an eccentric phenomenon that they hardly talked to each other going on underneath. Most of the time, they stayed in their rooms with doors closed. I never observed any of them asking help from others; maybe they sought it through Wechat or QQ.

People can chat with their friends any time. Is that the justification for the ignorance of people living around?

Chinese undergraduates, what's wrong with your social communication skill?

Before Several years ago, I had a experience was living with three Chinese undergraduates. On the first day I moved into my new room I knocked on their doors and said hello to them. They seemed introverted and a little bit cold. Considering their age, that was normal to me. After all, it was their first time to living abroad.

During the following months, I came to chat with them actively and the situation began to change. I found they were not introverted. Conversely, when we talked about some interesting topics they always took part  present much more actively than before. I thought I rebuild myself to be an approachable person successfully in front of them which resulted from my effort to communication( I am not sure what you are trying to say.  Did you think you should rebuild yourself? Or change?.  This sentence is very confusing)  However, I found an eccentric phenomenon at the same time, that they hardly talked with each other. Most of the time, they stayed in their rooms with the door closed. I had never seen any of them asking each other for advice/help asked for others something, maybe they would rather have asked their classmates for help through Wechat or QQ.

People can chat with their friends at any time, so is that a the justification to ignore the people around them? for the ignorance on people around?