The results for my two-word key phrase look like Google has discarded almost every page that doesn't have one or both words (or a weak synonym for at least one of them) in (preferably) the domain name or (at least) the URL.
This takes clear precedence over content or authority (a lot of the sites in the top 50 have neither).
I can't think this is permanent. If you want to buy a widget you might as well just enter widgetpurchase.com in the address bar yourself. If you can't find what you want there, go to obtaingadget.net. As a last resort, thingshop/widgets.co.uk.