Using a dash or a minus sign directly in front of a keyword tells eBay to avoid returning any results that have that keyword in the title or item-specifics.
So if you copy and paste your title exactly as shown, you are asking eBay to return item listings that have all the words in the title but that do not include "USA". Since your listing does have "USA" in the title, your listing is left out of the results.
Luckily for you, buyers will not be searching for your item that way.
If you drop the minus sign or dash from your search, your item does appear:
https://www.ebay.com/sch/i.html?_from=R40&_nkw=3x+Lightning+to+USB+Cable+USA+seller+Apple&_sacat=0&_...
