Perhaps you should try some spelling variations:
nam thuoc » nam thu, nha thuoc, cay thuoc
nam thuc » am thuc, nam thu, nam tu
day hanh » day nhanh, day thanh, dao hanh
hanh doi » thanh doi, hanh noi, hang doi
su sach » so sach, vu sach
hieu ve » hieu va, hieu van
doi cua » dai cua, hoi cua
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, ly nang, v nang

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((su sach) or (vu bach)) y nang x ho. hieu ve ((nam thuc) OR (nam thuoc)) day hanh doi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (vu bach)) y nang x ho. hieu ve ((nam thuc) OR (nam thuoc)) day hanh doi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su sach) or (vu bach)) y nang x ho. hieu ve ((nam thuc) OR (nam thuoc)) day hanh doi cua tre".
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (vu bach)) y nang x ho. hieu ve ((nam thuc) OR (nam thuoc)) day hanh doi cua tre*.