查了一下意思，好像不僅僅是忙，還有不得已之意。

When your hands are tied it means that you are prevented from doing something because some other authority prevents you from acting. This idiom can be applied to people or to organizations.

One may be unable to act because of existing rules, policies, higher-ranking officials or administrators, orders, or any other factors. The implication is that the situation is out of one’s control.