Perhaps you should try some spelling variations:
hieu vien » hieu hien, hieu viec, thieu nien
vien cac » vien bach, vien dai, vien da
ban hanh » ban hang
vai cua » dai cua, hai cua, lai cua
va hanh » van hanh, va thanh, va danh
cac xuc » cam xuc, cac nuoc, chat xuc
tu sach » thu sach, su sach, te sach
va lang » va nang, hoa lang
cua tre » cua te, cuu tre, cua triet
v lang » o lang, _ lang, van lang

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach ((v lang) OR (va lang)) xa hoi. hieu vien cac xuc ((va hanh) or (ban hanh)) vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((v lang) OR (va lang)) xa hoi. hieu vien cac xuc ((va hanh) OR (ban hanh)) vai cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((v lang) OR (va lang)) xa hoi. hieu vien cac xuc ((va hanh) or (ban hanh)) vai cua tre*".