It's only UK at the moment.
If you select Worldwide your listings "can" be found but searchers must select the worldwide box to get your items included in the search results.
On the other hand, if your items are unique and buyers use the right search terms and there are less than 30(?) domestic results then they will show up in the main search results. If there are more than 30 they will show up in a separate section following the domestic results.
Looking at your titles you might benefit from the extra visibility. The best thing to do is to go to the UK site and try searching for your items under the search terms you think buyers would use and see if your items come up. When you do this it's best if you are NOT logged in under your selling id.

"What else could I do? I had no trade so I became a peddler" - Lazarus Greenberg 1915
- answering Trolls is voluntary, my policy is not to participate.