Perhaps you should try some spelling variations:
nam thuoc » nam thuc, nam thu, nha thuoc
hanh dinh » thanh dinh, hinh dinh, hanh tinh
nang mai » nang ma, lang mai, nang cai
nang tai » hang tai, tang tai, sang tai
tu sach » thu sach, su sach, te sach
dinh cu » dinh cuu, dinh chuc, dinh chau
hieu va » lieu va, hieu qua
va hanh » van hanh, va thanh, va danh
cam tuc » cam xuc, cam tu, nam thuc
cu tre » cu tren, cua tre, cuu tre

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 y ((nang mai) OR (nang tai)) hoi. hieu va ((cam tuc) or (nam thuoc)) va hanh dinh cu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y ((nang mai) OR (nang tai)) hoi. hieu va ((cam tuc) OR (nam thuoc)) va hanh dinh cu tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach y ((nang mai) OR (nang tai)) hoi. hieu va ((cam tuc) or (nam thuoc)) va hanh dinh cu tre*".