Supplies for one travelling through Tahiti and Canada on vacation (7)

'supplies' is the definition.
I don't know anything about this answer so I cannot judge whether it can be defined by this definition.

'one travelling through tahiti and canada on vacation' is the wordplay.
'one travelling through' becomes 'via' (I've seen this in other clues).
'tahiti' becomes 'ti' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'and' says to put letters next to each other.
'on vacation' means to remove the middle letters (after the inside letters have vacated the word).
'canada' with its centre taken out is 'ca'.
'via'+'ti'+'ca'='VIATICA'

'for' acts as a link.

Can you help me to learn more?