First you must find out the clause of the quality problems and furnish sufficient evidence.
首先你的查查有关质量问题的条款,并提供足够的证据。
The Ambassador's wife went on asking questions, when she suddenly noticed a big hole in her husband's hat.
大使夫人继续提出问题,她突然又发现丈夫的帽子上有个洞。