Says there's nothing in one's bad habits (6)
I believe the answer is:
voices
'says' is the definition.
(voicing is a kind of saying)
'nothing in one's bad habits' is the wordplay.
I cannot really understand how this works, but
'nothing' could be 'o' (looks like zero - 0) and 'o' is present in the answer.
'habits' could be 'vices' (I have seen 'Bad habits ' mean 'vices' so perhaps 'habits' could also mean 'vices') and 'vices' is found in the leftover letters.
No letters remain.
This may be the basis of the clue (or it may be nonsense).
'there's' is the link.
Can you help me to learn more?
(Other definitions for voices that I've seen before include "Sounds of people" , "They may be audible" , "Expressed opinions; utters" , "Speaks" .)