如何管理這些員工

Firstly you have to find out what cause this happen. If they hate/dislike each other because they dont get along with each other. Honestly, u may not help much but still you can talk to them individually to see what is going on.

If they like their workmates, then it is a lot easier, offical and unoffical activities such as lunch together, play badminton, dinner after work.

I face this kind of problem as well.

如果是我的話我會静静的找原因之餘, 多的同的同事一起搞活動, 等大家的感情可進一步, 當然你本人要在公在私都要有一個平衡的作用, 大家都在俾面大家之嗎, 你懂我的意思嗎.