Perhaps you should try some spelling variations:
thanh hiep » thanh hien, thanh thieu, thanh vien
thuc dan » thuc hanh, hoc dan
hiep cua » tiep cua, hieu cua, hien cua
hieu van » hieu va, thien van, lieu va
tu sach » thu sach, su sach, te sach
ky tang » ky nang, ky dang, kho tang
tang ma » mang may, tang van
sach ky » sac ky, sach y, sach ty
xuc va » duc va, tuc va, luc va
ma hoi » mai hoi, xa hoi, ma hoa
cua te » cua tu

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 tang ma hoi. hieu van nam ((xuc va) or (((thuc dan) OR (thuc vat)))) thanh hiep cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky tang ma hoi. hieu van nam ((xuc va) OR (((thuc dan) OR (thuc vat)))) thanh hiep cua te*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky tang ma hoi. hieu van nam ((xuc va) or (((thuc dan) OR (thuc vat)))) thanh hiep cua te*".