Perhaps you should try some spelling variations:
nam thuoc » nam thu, nha thuoc, cay thuoc
nam thuc » am thuc, nam thu, nam tu
hanh tai » thanh tai, hang tai, han tai
te sach » toc sach
va hanh » van hanh, va thanh, va danh
hieu le » hieu ve, hieu he, hieu ly
hoc doi » hoc dai, hoc noi, hoc moi
ty hang » ly hang, thi hang, thu hang
tai va » thai va, mai va, tri va
thiet » thieu

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ((ty hang) or (ty xang)) hoc doi. hieu le ((nam thuc) or (nam thuoc)) va hanh tai va thiet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ((ty hang) OR (ty xang)) hoc doi. hieu le ((nam thuc) OR (nam thuoc)) va hanh tai va thiet.
• Adding a wildcard symbol may retrieve word variants: te sach ((ty hang) or (ty xang)) hoc doi. hieu le ((nam thuc) or (nam thuoc)) va hanh tai va thiet*.