Perhaps you should try some spelling variations:
va thieu » va thiet, va hieu, va tieu
hanh vai » hanh vi, hanh va, hanh tai
sach ty » sach y, sach tu, sach thu
hieu ve » hieu va, hieu van
te sach » toc sach
lai hoi » dai hoi, lai hoa, lai roi
mai hoi » mai khoi, dai hoi, mai doi
ty nang » ky nang, ty xang, ty hang
ve chat » va chat, van chat
luc va » duc va, loc va
tuc va » thuc va, truc va, tuc xa
vai va » mai va, dai va, hai va

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ty nang ((mai hoi) OR (lai hoi)). hieu ve chat ((luc va) or (tuc va)) hanh vai va thieu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ty nang ((mai hoi) OR (lai hoi)). hieu ve chat ((luc va) OR (tuc va)) hanh vai va thieu*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ty nang ((mai hoi) OR (lai hoi)). hieu ve chat ((luc va) or (tuc va)) hanh vai va thieu*".