I don't know whether this is a problem or not. I myself am living in Tokyo and MKLocalSearch returns mapItems in Tokyo, say Apple Shinjuku, Apple Omotesando, Apple Ginza and so on, on a live preview as well as on a real iOS device. I also ran the code I downloaded from your server and I got the same result. Irrespective of the region set by the code, MKLocalSearch seems to search places where my Mac or iOS device actually exists, in my case, it is Tokyo. After having googled, I finally got the same result as you explained in your lesson if I set the region again by repeating the following code instead of "request.region = mapView.region",
let centerCoordinate = CLLocationCoordinate2D(latitude: 37.76666, longitude: -122.427290)
let span = MKCoordinateSpan(latitudeDelta: 0.1, longitudeDelta: 0.1)
let region = MKCoordinateRegion(center: centerCoordinate, span: span)
request.region = region
Anyway, I'm enjoying this new course!!