Perhaps you should try some spelling variations:
thanh cau » thanh chau, thanh mau, nhanh cau
nam thuoc » nam thuc, nam thu, nha thuoc
thuoc van » thuoc va, thuc van, thuoc ban
soc thiet » hoc thiet, so thiet, toc thieu
sach thi » sach thu, sach tai, sach tham
van hanh » van thanh, ban hanh, van anh
hanh tai » thanh tai, hang tai, han tai
qua nam » quan nam, cua nam, quang nam
tai soc » tai so, tai hoc, thai son

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 thi) or (sach thieu)) thanh cau hoi. hieu qua nam thuoc van hanh tai soc thiet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach thi) OR (sach thieu)) thanh cau hoi. hieu qua nam thuoc van hanh tai soc thiet.
• Adding a wildcard symbol may retrieve word variants: tu ((sach thi) or (sach thieu)) thanh cau hoi. hieu qua nam thuoc van hanh tai soc thiet*.