Unsearchable; incapable of being searched into and understood by inquiry or study; impossible or difficult to be explained or accounted for satisfactorily; obscure; incomprehensible; as, an inscrutable design or event.
In my mind's eye, Shakespeare is a huge, hot sea-beast, with fire in his veins and ice on his claws and inscrutable eyes, who looks like an inchoate hump under the encrustations of live barnacle-commentaries, limpets and trailing weeds. A. S. Byatt
People like to say that East Asians in general, and Japanese in particular, are not very expressive: there's that term 'inscrutable.' But often, Europeans just don't get the Asian codes. Believe me, the message is being expressed OK. David Mitchell