Perhaps you should try some spelling variations:
nam thuoc » nam thuc, nam thu, nha thuoc
hau theo » cau theo, dau theo, hanh theo
hanh hai » thanh hai, nhanh hai, hang hai
thuoc va » thuc va, thuoc ma, thuong va
ly nang » ky nang, ly hang, ly vang
hieu va » lieu va, hieu qua
va hanh » van hanh, va thanh, va danh
co sach » bo sach, cuon sach, hoc sach
hai hau » hai chau, dai hau, hai hai
so sach » so sanh, bo sach, hoc sach
va nam » van nam, ha nam, va nay
y nang » ky nang, v nang, may nang

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((so sach) OR (co sach)) ((y nang) or (ly nang)) cau hoi. hieu va nam thuoc va hanh hai hau theo~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((so sach) OR (co sach)) ((y nang) OR (ly nang)) cau hoi. hieu va nam thuoc va hanh hai hau theo.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((so sach) OR (co sach)) ((y nang) or (ly nang)) cau hoi. hieu va nam thuoc va hanh hai hau theo".
• Adding a wildcard symbol may retrieve word variants: ((so sach) OR (co sach)) ((y nang) or (ly nang)) cau hoi. hieu va nam thuoc va hanh hai hau theo*.