有些投資公司是通過收購, 分拆其他公司來賺錢, 其一般運操作和原理是什麼呢?

The buy action can be classified as 兼併（merger）or 收購（acquisition）; while the sell action be 解散（dissolution）、分拆（divoicement）、放棄（divestiture）or 分立（Spin-offs）. Each of them has well defined process and have substantial differences in many aspects.

Putting both sides together the model is given with a beautiful name "資產重組". To explain them even briefly may need a thousand words on each topic. You can find their definitions from this "高盛财经词典 - 英汉对照":
http://www2.goldmansachs.com/hkchina/dictionary/ec/dictionary_ec_a.html


Simply speaking they are all done for one single purpose: 帶來更高的回報率!