* It's a misspelling or variation of another surname. There might be a similar-sounding surname with a different origin.
* It's a recently created surname. Some people choose to create new surnames for personal reasons.
* It's a fictional surname. It could be used in a book, movie, or other creative work.
To get a better understanding of the surname's origin:
1. Check for variations: See if there are any similar-sounding surnames.
2. Consider the person's background: If you know the person's ethnicity or heritage, that could provide clues.
3. Research online: Search for the surname on genealogy websites, forums, or other resources.
Without more information, it's difficult to determine the origin of the surname "Sinohui."