Perhaps you should try some spelling variations:
lang van » dang van, tang van, hoang van
cham duc » pham duc, cham soc, pham duy
hanh vai » hanh va, hanh tai, hanh van
bo sach » co sach, hoc sach
lang ha » long ha
hieu va » lieu va, hieu qua
va cham » va chat, va tham
cua tre » cua te, cuu tre, cua triet

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

• Performing a fuzzy search may retrieve terms with similar spellings: bo sach y ((lang van) or (lang ha)) hoi. hieu va cham duc va ((hanh vai) OR (hanh vi)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: bo sach y ((lang van) OR (lang ha)) hoi. hieu va cham duc va ((hanh vai) OR (hanh vi)) cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "bo sach y ((lang van) or (lang ha)) hoi. hieu va cham duc va ((hanh vai) OR (hanh vi)) cua tre*".