您搜索了: 那是另一回事 (简体中文 - 英语)

如果一国选择承担具体条约义务以这种方式约束自己，那是另一回事。
if a state chose to bind itself in that way by undertaking specific treaty obligations, it was a different matter.

原来是这么一回事
it turns out that this is the case