A couple of messages had mysteriously disappeared.
几条信息神秘地消失不见了。
2ADJ-GRADED [verb-link ADJ]爱故弄玄虚的;神秘的 If someone is mysterious about something, they deliberately do not talk much about it, sometimes because they want to make people more interested in it. 爱故弄玄虚的;神秘的
As for his job — well, he was very mysterious about it. [+ about]