母は帰りが遅くなった理由を息子に問いただした。
The mother questioned her son closely about why he had come home late.
記者たちは大臣に資金の使い道を問いただした。
The reporters pressed the minister to explain how the funds had been used.
納得がいかない点は、その場で担当者に問いただすべきだ。
You should ask the person in charge about anything you're not satisfied with right there and then.