How you search can affect which items appear in a search. Altering the way you search can often show you different results, which may or may not be better in each case.
Changing from "default" to "worldwide" item location will show you more international sellers' items.
If a seller does not ship to the location you are using to calculate shipping, the seller's items will not be shown.
If you are using a "lowest price" sort, you may see a message at the top of the results:
To see all the results you must use the "View all results" link, otherwise you may be seeing only those results that eBay deems "relevant".
If you are using an ad blocker you may be blocked from seeing sponsored listings. In most cases you will still see the non-sponsored "organic" version of the listing, but if you also use "Best Match" sort, eBay may not display both sponsored and organic listings, and you may miss both.
If you search using certain keywords, eBay will often steer the search into a particular category where most sales for such searches occur; if you want to see all the possible results in all categories, you may need to change the category manually and search again, or use different keywords.
eBay's search tries to find the items that most users are searching for (even if users do not use the correct spelling or the right keywords), and to hide listings that are not what most users are looking for (even if those listings do have all the correct keywords); eBay's search does not always succeed (and sometimes it fails spectacularly), but eBay certainly has an incentive to provide search results that eBay thinks will ultimately result in the most possible sales.
