Unrecorded Phantom Gems

You need a certain third party program to do that, you can't register in Yahoo and Mercari. Some are monthly paid services with image functionality and proper notifications, or you can develop API yourself to return only the title of the listing as a notification. Of course paid apps has better looking notifications and proper image tracking, but I prefer it the cheap way out.

The reason why 3600 over keywords is because each seller can list the exact same Plarail product with a different name. For example: 転車台 (Turntable) can be written as てんしゃだい or てんしゃ台 or ターンテーブル. And 寝台特急 (Shindai Express) can be listed as ドボソ in the Mie dialect, and しんだいとっきゅう. This 3600 over keywords list is still growing today

I am an app developer who deals with aggressive self-learning API that registers thousands of seller patterns, it can be somewhat called artificial intelligence. So I use my API libraries to store keywords, and everytime a new listing is listed, the app sends notifications to my own mobile device. However not every listing with unusual content gets detected because the seller just writes Plarail "プラレール" or simple writes mass bulk "大量セット". Say if I register "大量セット", it will return garbage listings with common junk so it is excluded from the list.