Green’s Dictionary of Slang

dook n.2

[dookie n. (1)]

(US campus) something unpleasant or worthless.

[US]Eble Campus Sl. Oct. 4: dook – [...] ‘Bill’s excuse is a bunch of dook’.
[US]Eble Sl. and Sociability 41: Dook ‘something unpleasant or worthless’ and dookie ‘someone obnoxious’ omit the front glide pronounced before the vowel in duke (as in rival Duke University) to make the word sound more derogatory.
[US]Eble Campus Sl. Apr. 3: dook – feces.

In phrases

not know dook (about) (v.)

(US) to know nothing (about).

[US]D. Jenkins Stick a Fork In Me 69: ‘When you hear football talk from the big-timers, keep in mind that they really don’t know dook about the game, they just act like they do’.