หัวแข็ง hŭua kăeng (hard head): cứng đầu

describe a person who does not listen to other people's opinions, convincing or advice. They have their own thoughts. They are not flexible or open-minded.

นหูเบา: dễ tin người = gullible

describe a person who is easily convinced or willing to believe too readily.

vd: เขาเป็นคนหูเบา ทำให้เขาเชื่อสิ่งที่เขาได้ยินได้ง่ายๆ
He is a gullible person, making him easy to believe what he hears.