behind closed doors

基本解释

If your people are dying from this, do not put this behind closed doors. Go save them.
如果你的人民正在因此而死亡，不要把问题关在门外，而要去拯救他们。
Behind closed doors, a group of men—they have sent many of the women and children out of the city—fearfully debated what will happen.
在那些紧闭的门后，一群男子——他们已经把大多数妇女和儿童送出城外——惶惶不安地讨论将会发生些什么。
But many Nigerians say that if the president really wants to hold proper polls, he should be out campaigning among the masses instead of schmoozing behind closed doors.
不过许多尼日利亚民众表示，如果总统真的想获得足够的票选，就应该到民众当中开展竞选活动，而不是关起门闲谈。

"The health care scheme, under reconciliation, means decisions made by the government, behind closed doors, against the wishes of the American people."
But Nujood says most of Yemen's child brides still suffer behind closed doors and black veils.
"Whatever deals that are being done, they are certainly being done behind closed doors,".

We can only surmise the precise content of all those conversations going on behind closed doors.
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If something happens behind closed doors, it is hidden or kept secret from public view.