Perhaps you should try some spelling variations:
thanh vai » thanh hai, thanh van, thanh tai
va thieu » va thiet, va hieu, va tieu
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va, hieu van
tu sach » thu sach, su sach, te sach
dai hoi » dai hoc, dai hai, dai moi
mai hoi » mai khoi, lai hoi, mai doi
xuc va » duc va, luc va, xac va
tuc va » thuc va, truc va, tuc xa
vai va » mai va, dai va, hai va
ve cam » ve cham, ve cac, va cam

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 ky nang ((mai hoi) or (dai hoi)). hieu ve cam ((xuc va) OR (tuc va)) thanh vai va thieu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang ((mai hoi) OR (dai hoi)). hieu ve cam ((xuc va) OR (tuc va)) thanh vai va thieu.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang ((mai hoi) or (dai hoi)). hieu ve cam ((xuc va) OR (tuc va)) thanh vai va thieu".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang ((mai hoi) or (dai hoi)). hieu ve cam ((xuc va) OR (tuc va)) thanh vai va thieu*.