Perhaps you should try some spelling variations:
tam thuc » tham thuc, am thuc, nam thuc
vanh dai » van dai, vanh tai, lanh dao
cay vanh » cay lanh, cay xanh, cac van
thuc cay » thuc day, thuc can, thuc cao
su sach » so sach, vu sach
nang ma » tang ma, nang cao, mang may
sang ma » tang ma, sang tao, mang may
sach v » sach va, sach y, sach 2
va tam » van tam, va tham, va tac

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 v ((nang ma) or (sang ma)) hoi. lieu va tam thuc cay vanh dai ((cua su) OR (qua su))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach v ((nang ma) OR (sang ma)) hoi. lieu va tam thuc cay vanh dai ((cua su) OR (qua su)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach v ((nang ma) or (sang ma)) hoi. lieu va tam thuc cay vanh dai ((cua su) OR (qua su))".
• Adding a wildcard symbol may retrieve word variants: su sach v ((nang ma) or (sang ma)) hoi. lieu va tam thuc cay vanh dai ((cua su) OR (qua su))*.