Perhaps you should try some spelling variations:
nam thuoc » nam thuc, nam thu, nha thuoc
van giang » manh giang, tran giang, dan gian
sang mai » sang ma, sang tai, lang mai
va gianh » va gian, va giai, va thanh
lai cua » dai cua, hai cua, lai chau
cua tre » cua te, cuu tre, cua triet
hieu ve » hieu va, hieu van
mai hoi » mai khoi, dai hoi, lai hoi
ky sang » ky nang, ky dang, ky tang
sac ky » cac ky, sai ky
te sac » te sach, te cac, te san

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

• If you are trying to use Boolean operators, they must be ALL CAPS: te sac ky sang mai hoi. hieu ve ((nam thuoc) OR (cam xuc)) ((va gianh) OR (van giang)) lai cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sac ky sang mai hoi. hieu ve ((nam thuoc) or (cam xuc)) ((va gianh) OR (van giang)) lai cua tre~".
• Adding a wildcard symbol may retrieve word variants: te sac ky sang mai hoi. hieu ve ((nam thuoc) or (cam xuc)) ((va gianh) OR (van giang)) lai cua tre*.