Even 'linguists' have to surrender to this puzzle

The challenge is so difficult that even language enthusiasts have to give up.

This puzzle is so difficult that even the "king of Vietnamese" was stunned. Combine the words c/h/ố/á/t/C/l into meaningful phrases.

What word is this?

Leave your answer in the comments section and check how many answers match.

Giang Pham

Source: https://vtcnews.vn/nguoi-sanh-ngu-cung-phai-dau-hang-voi-cau-do-nay-ar972367.html