Perhaps you should try some spelling variations:
cua tre » cua te, cuu tre, cua triet
cac hoi » cac thoi, cac khoi, cau hoi
ky tang » ky nang, ky dang, kho tang
tang ma » mang may, tang van
hieu ve » hieu van
hieu va » lieu va, hieu qua
dao va » dao van, do va, cao va
tu sac » tu sach, tu cac, tu san
sac ky » cac ky, sai ky
ma hoi » mai hoi, xa hoi, ma hoa

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sac ky tang ma hoi. ((hieu ve) or (hieu va)) cac hoi va ((dao va) OR (tao va)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sac ky tang ma hoi. ((hieu ve) OR (hieu va)) cac hoi va ((dao va) OR (tao va)) cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sac ky tang ma hoi. ((hieu ve) or (hieu va)) cac hoi va ((dao va) OR (tao va)) cua tre*".