Perhaps you should try some spelling variations:
thuoc dat » thuoc bat, thuoc dac, thuoc dang
nam thuoc » nam thuc, nam thu, nha thuoc
dat thanh » dao thanh, dat khanh, dang thanh
hoc sach » hoc sinh, hoc cac, hoc anh
hieu van » hieu va, thien van, lieu va
thanh vi » hanh vi, thanh va, thanh ve
cau treo » cau theo, cau tren, cau triet
tu sach » thu sach, su sach, te sach
nang ma » tang ma, sang ma, nang cao
ma hoi » mai hoi, xa hoi, ma hoa
vi cau » va cau, ve cau, di cau

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) or (hoc sach)) ky nang ma hoi. hieu van nam thuoc dat thanh vi cau treo~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (hoc sach)) ky nang ma hoi. hieu van nam thuoc dat thanh vi cau treo.
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (hoc sach)) ky nang ma hoi. hieu van nam thuoc dat thanh vi cau treo*.