Constructive criticism improves a person's behavior, encouraging positive changes. Whereas destructive criticism condemns and discourages the person.  Destructive criticism demeans, discredits and hurts people. In contrast, constructive criticism improves a specific behavior without personal attacks.Their self-esteem remains intact. Your reason for critiquing someone's work or behavior affects how you deliver feedback. If you have an ulterior motive besides wanting to help the person improve, thats come across as overtly negative. Reflect on whether the criticism you intend to impart will actually be productive.  Good intentions do not always get a positive response. For example, if your friend has gained a lot of weight since you last saw each other, telling her she should lose weight for her health's sake probably won't fall on receptive ears and, in fact, she may feel hurt. Criticizing is one of those domains where intentions are less important than what you actually say and do. Instead of acting on impulse, be thoughtful and ask yourself how it would sound if you told this person what you’re thinking. Are the words you choose appropriate? What about the underlying social politics? What about yourself? For example, if you want to criticize your friend about her weight and you're naturally thin, think about how she may feel to receive this feedback from you, someone who has never struggled to lose weight nor experienced weight-based discrimination. If someone requests feedback and is willing to change, then constructive criticism is warranted. Ask yourself if the person would be better off receiving constructive criticism. Would it have a positive impact on their life? Unsolicited criticism could be hurtful. If the issue is relatively minor, such as a situation where you don't like your friend's wardrobe because she wears too much pink and you want to tell her, it may best not to say anything...unless you feel this situation is disadvantageous to or hurting her in some way. It's important to use criticism...

How would you rephrase that briefly using Vietnamese?
Chú ý sự khác biệt giữa phê bình mang tính xây dựng và phê bình mang tính phá hoại. Có thiện chí. Liệu lời phê bình có lý do chính đáng không? Quyết định xem bạn có phải là người có quyền để phê bình. Chọn thời gian và địa điểm.