Perhaps you should try some spelling variations:
thuoc dang » thuoc dung, thuoc khang, thuc dan
dang thanh » dong thanh, dang hanh, hoang thanh
thanh doi » thanh loi, thanh moi, thanh do
nam thuoc » nam thuc, nam thu, nha thuoc
toc sach » hoc sach, doc sach, thuoc sach
toc sac » toc san, hoc sach, doc sach
doi cua » dai cua, hoi cua
hieu va » lieu va, hieu qua
cua tre » cua te, cuu tre, cua triet
nang ma » tang ma, sang ma, nang cao
nang xa » nang x, lang xa, mang xa
va nam » van nam, ha nam, va nay

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: ((toc sac) or (toc sach)) ky ((nang xa) OR (nang ma)) hoi. hieu va nam thuoc dang thanh doi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((toc sac) OR (toc sach)) ky ((nang xa) OR (nang ma)) hoi. hieu va nam thuoc dang thanh doi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((toc sac) or (toc sach)) ky ((nang xa) OR (nang ma)) hoi. hieu va nam thuoc dang thanh doi cua tre".
• Adding a wildcard symbol may retrieve word variants: ((toc sac) or (toc sach)) ky ((nang xa) OR (nang ma)) hoi. hieu va nam thuoc dang thanh doi cua tre*.