Perhaps you should try some spelling variations:
hieu vien » hieu hien, hieu viec, thieu nien
cau tren » cu tren, dau tren, ca tren
vien cac » vien bach, vien dai, vien da
ky lang » ky nang, ky dang, ky tang
lang xa » lang ha, dang xay, lang van
cac dac » cac dan, cac dai, cac bac
va hanh » van hanh, va thanh, va danh
cua tre » cua te, cuu tre, cua triet
so lang » so dang, hoa lang, hoi lang
o lang » hoa lang, hoi lang
dac va » duc va, day va, dat va

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: ((so lang) or (o lang)) ky lang xa hoi. hieu vien cac dac va hanh vi ((cua tre) or (cau tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((so lang) OR (o lang)) ky lang xa hoi. hieu vien cac dac va hanh vi ((cua tre) OR (cau tren)).
• Adding a wildcard symbol may retrieve word variants: ((so lang) or (o lang)) ky lang xa hoi. hieu vien cac dac va hanh vi ((cua tre) or (cau tren))*.