Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
van nhan » van phan, van thanh, danh nhan
hanh tai » thanh tai, hang tai, han tai
duc tre » duoc tren, duc tien
ky dang » ky nang, ky danh
dang ma » dang mau, dang mam, dang mat
cuc tre » cua tre, cuu tre, cuc thue
loc va » hoc va
te sac » te sach, te cac, te san
sac ky » cac ky, sai ky
ma hoi » mai hoi, xa hoi, ma hoa
luc va » duc va, tuc 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 sac ky dang ma hoi. hieu van nhan ((luc va) or (loc va)) hanh tai ((cuc tre) or (duc tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sac ky dang ma hoi. hieu van nhan ((luc va) OR (loc va)) hanh tai ((cuc tre) OR (duc tre)).
• Adding a wildcard symbol may retrieve word variants: te sac ky dang ma hoi. hieu van nhan ((luc va) or (loc va)) hanh tai ((cuc tre) or (duc tre))*.