Excluding countries from scans.

Stockcharts does offer symbols for exchanges in China. Available countries are listed here:

https://support.stockcharts.com/doku.php?id=scans:reference:ticker_properties

But, some Chinese companies are listed on US exchanges (like BABA). You can't exclude those with a single condition. You could exclude them as you come upon them by adding [symbol is not ....] statements, one per symbol to your scan(s), if you think it's worthwhile.