Plucks trimmed, variable, oddly drippy stuff primarily from these bran tubs (5,4)

'these bran tubs' is the definition.
The definition suggests an adverb but the answer is not.

'plucks trimmed variable oddly drippy stuff primarily' is the wordplay.
'trimmed' means to look at the middle letters (the external letters are trimmed from the word).
'variable' becomes 'y' (algebra).
'oddly' means one should take alternating letters (letters in the odd-numbered positions are used).
'primarily' indicates taking the first letters.
The central letters of 'plucks' are 'luck'.
The first letter of 'stuff' is 's'.
The alternate letters of 'drippy' are 'dip'.
'luck'+'y'+'dip'+'s'='LUCKY DIPS'

'from' acts as a link.

Can you help me to learn more?