20分!! via VS through

'Via' is a prep. - mean travelling or sent thru.
e.g.1 - We flew to Athens via Paris.
e.g 2 - I sent a parcel to customer via Fedex express.( most of time it sent thru a 'media'

'Through' - can be a prep. or adv or adj. see how to apply in a sentence. From your question, we compare the usage as a prep.
'Through' consists different meanings
1) thing from one side to another side.
e.g. Waters flows through this pipe.
This describes the action of the object without any 'media'.
2) by way of, by means of..
e.g. She climbed in through the window.
This describes how the subject get the way from one place to another place.

So, the application of via and thru is not same. Hope the above can help.

其實係無乜分別
只係via佢原來唔係come from english而係come from latin
via同through都係有藉著, 透過, 通過既意思
亦即係
please contact me through e-mail/ please contact me via e-mail 都可以~

應該用通過