Adverb
In a mysterious manner.
Source: Webster's dictionaryThe poets have been mysteriously silent on the subject of cheese. G. K. Chesterton
. . . the rich ate and drank freely, accepting gout and apoplexy as things that ran mysteriously in respectable families . . . George Eliot
War puts its questions stupidly, peace mysteriously. André Malraux
"There is something more mysteriously attractive than beauty: it is corruption.” (Garden of Tortures) Octave Mirbeau
But the mind travels far - and mysteriously - in sleep. Mary Augusta Ward
There is nothing more thrilling in this world, I think, than having a child that is yours, and yet is mysteriously a stranger. Agatha Christie