This unit is built into a bucket, so as it combs the soil it tosses the sticks and rocks into it, then you rais it up and dump out the bucket.
Thats the big difference from a harley rake, you still have to go and pick stuff up. This machine breaks up the clumps of dirt. Once the bucket is full, I sometimes lift it up and tip it forward, run the unit and it sifts out all the dirt and stuff and sort of shreds the clumps of sod you have in it.
I'm sure if you google it you will find a video on one.
I think the technical name is a landscape rake, rock hound might be a brand name like "klenex" is technically "tissue" etc...