Perhaps you should try some spelling variations:
thanh dai » thanh hai, thanh tai, thanh dat
hieu van » thien van, lieu va, hieu ve
cua tre » cua te, cuu tre, cua triet
ky dang » ky nang, ky danh
dang ha » dong ha, dung ha, lang ha
hieu va » lieu va, hieu qua
luc va » duc va, tuc va, loc va
tu sac » tu sach, tu cac, tu san
xuc va » duc va, tuc va, xac va
sac ky » cac ky, sai ky
ha hoi » hoa hoi, ha noi, xa hoi

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 dang ha hoi. ((hieu van) OR (hieu va)) lam ((xuc va) or (luc va)) thanh dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sac ky dang ha hoi. ((hieu van) OR (hieu va)) lam ((xuc va) OR (luc va)) thanh dai cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sac ky dang ha hoi. ((hieu van) OR (hieu va)) lam ((xuc va) or (luc va)) thanh dai cua tre*".