Dad picked up bargains with vegetables (8)
I believe the answer is:
parsnips
'vegetables' is the definition.
(parsnip is a kind of vegetable)
'dad picked up bargains' is the wordplay.
I cannot quite see how this works, but
'dad' could be 'pa' (synonyms) and 'pa' is found within the answer.
This may be the basis of clue (or it may be nonsense).
'with' is the link.
Can you help me to learn more?
(Other definitions for parsnips that I've seen before include "food" , "Fine words don't butter them" , "roots" , "Snip spar with the vegetable" , "Things growing in garden" .)