If you live in Melbourne's west and are expecting a parcel to be delivered this week, don't hold your breath.

Police are searching for a man who stole a delivery van full of packages while it was parked in front of a house in Sunshine North last week - while an unsuspecting courier was still in the van.

The courier was in the back of the van sorting through parcels while it was parked on Troon Crescent when a man walked up to the driver's door about 10.50am on Wednesday, January 3.

The thief broke into the van and drove off - causing the courier to fall through the back door of the van and onto the road.