First, read the English article below.

If he only calls once a week and barely has anything to say, that's probably not a good sign. However, if he spontaneously texts, emails, and calls on a regular basis, then he probably can't get you out of his mind, meaning he loves you. However, every guy is different. Maybe he's an introvert, and he doesn't like to spend every minute with another person, even someone he loves. Make sure you try to figure out what kind of person he is before jumping to conclusions. That is when you get together, does he ask questions about you and your day? Does he seem to genuinely care about what's going on in your life? If he's truly interested in what you're doing, he likely cares about you. Of course, guys (and people) in general are going to forget things, including important dates and past conversations. But if he makes an effort to remember important dates, and he is paying attention to the conversations you have by bringing them up later, then he is likely in love with you. To truly fight with someone, you need to care about that person, and then find a way to make amends. If he's not willing to fight or if he just brushes off arguments with a shrug, he may not care that deeply about you. You don't necessarily need to have knock-down, drag-out fights. But you both need to be able to express your opinions and thoughts, even if it leads to an argument. If he doesn't seem willing to engage, he may not be into you. That is if he starts using "we" on a regular basis, rather than just "I," that could be a sign he loves you. "We" indicates he's started thinking of you as a unit, a couple, which means he's starting to commit to you being together. If you have your own language, including pet names and inside jokes, that's a good sign. It means that he cares enough about you to fully engage in the relationship. If he has a pet name for you (and only you), it likely means he's at least falling for you. If you're in a healthy relationship, you can simply have a conversation about your feelings. Talk about what you like about... 

Now, please write a short abstract for it in Vietnamese. Abstract:
Quan sát xem anh ấy liên lạc với bạn như thế nào. Chú ý những điều anh ấy quan tâm. Xem thử anh ấy có ghi nhớ không. Để ý xem liệu anh ấy có quan tâm đến mức muốn tranh luận cho ra lẽ không. Chú ý đến ngôn ngữ của anh ấy. Để ý xem hai bạn có những ngôn từ chung không. Đừng ngại hỏi.