Perhaps you should try some spelling variations:
dong thanh » truong thanh
thuc dong » thuoc dong, thuc dung, phuc dong
va triet » va trien, ve triet, cua triet
thanh va » thanh van, hanh va, thanh ha
nam thuc » nam thuoc, am thuc, nam thu
so sach » so sanh, bo sach, co sach
sang ma » nang ma, sang tao, mang may
tang ma » mang may, tang van
hieu he » hieu ve, hiem he, hieu le
he nam » ha nam, nghe nam
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: so sach y ((sang ma) or (tang ma)) hoi. hieu he nam thuc dong thanh va ((va triet) or (va thiet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach y ((sang ma) OR (tang ma)) hoi. hieu he nam thuc dong thanh va ((va triet) OR (va thiet)).
• Adding a wildcard symbol may retrieve word variants: so sach y ((sang ma) or (tang ma)) hoi. hieu he nam thuc dong thanh va ((va triet) or (va thiet))*.