Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
lam truc » lam truoc, nam truc, lam thuoc
va thanh » gia thanh, ban thanh, va tinh
thanh di » thanh doi, thanh de, thanh do
cua viet » ca viet, hoa viet, cua dieu
su sach » so sach, vu sach
nang ma » tang ma, sang ma, nang cao
van lam » van nam
truc va » thuc va, thuc vat, trung va
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: ((su sach) or (thu hoach)) ky nang ma hoi. hieu van lam truc va thanh di ((cua viet) OR (cua vat))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (thu hoach)) ky nang ma hoi. hieu van lam truc va thanh di ((cua viet) OR (cua vat)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su sach) or (thu hoach)) ky nang ma hoi. hieu van lam truc va thanh di ((cua viet) OR (cua vat))".
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (thu hoach)) ky nang ma hoi. hieu van lam truc va thanh di ((cua viet) OR (cua vat))*.