Not very bad - you can overlook it (8)
I believe the answer is:
passable
'overlook it' is the definition.
I can't tell whether this defines the answer.
'not very bad you can' is the wordplay.
'not very bad you' becomes 'pass' (I can't explain this - if you can you should give a lot more credence to this answer).
'can' becomes 'able' (I've seen this in other clues).
'pass'+'able'='PASSABLE'
Can you help me to learn more?
(Other definitions for passable that I've seen before include "examinations should be!" , "not hogging the road" , "okay?" , "Barely adequate" , "Fairly good but not outstanding" .)