What is this great dog from resue centre

I brought this brilliant dog years ago from the lost dogs home in Melbourne Vic Australia. The Vet’s didn’t know the breed. We thought we may see something similar in Victoria and did around Beechworth, but never again Southern parts of Australia. Years later I was in Holland and I saw the breed a lot in the parks over there, I asked some people and they said didn’t know. Just a common dog over there. He is a medium sized dog and had natural sheep herding ability. He was not as interested in other dogs so much, but is gentle with them. Loved people and cats, possums, bids, rats, kangaroos etc, just loved the chase. Strong could walk for hours. Back in Australia they have a larger breed in Tasmania called a Smithfield, also a working dog and some look the same but bigger. Also he looks like a small version of a Bearded Collie and the ancestry comes from this breed.