Take care & think carefully before using this.I've bought a bag of Top Soil (Westland is the make) from Asda (the Uk's Walmart).
One of my previous jobs was driving various size tipper trucks, both rigid & semi articulated & one of the common jobs was what was called "muck away." This meant you moved soil, (muck,) from a site. Sometimes this soil was moved to a location that needed soil & sometimes it was moved to premises from which it was sold on from.
Top soil is just what it says, the top layer of soil on any site, be that a garden, a farm, or an old factory site. I have moved so called top soil by the ton. An HGV 1 moves around 25 to 30 ton per load.) And I have moved multiple loads per day to sites where it will then be sold on by the truck load to landscapers, developers etc As well as to other retailers who will then sell it on in smaller quantities to people such as yourself & a fair tonnage of that will come from locations that you would not want your T to inhabit.