My comprehension of German leaves much to be desired. I look at this moment at German interviews, naturally, of Quasthoff. The story is true, he confirms in one interview, that he was contacted about a one-time singing engagement by the last people you would expect: the company that manufactures the proprietary form of thalidomide sold in Germany. As one quickly learns when getting acquainted with this musician, Quasthoff was born a thalidomide-scandal infant, with the full array of the well-known, shocking birth defects. So here was this Big Pharma in Deutschland, inquiring if they could not possibly interest Quasthoff in singing at their corporate Christmas party one year?

Quasthoff's response: "IHR HABT SIE WOHL NICHT ALLE!" Yes, I realize this means NO. It looks like very simple vocabulary, but not the kind I learned from song/Lied lyrics.

So: "you truly don't have all of it." ?
Not dealing with a full deck?    Lost your marbles?    Clueless? (yes, I daresay I must be clueless...)