Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
vat hanh » vat thanh, van hanh, va hanh
nam thuc » nam thuoc, am thuc, nam thu
cua tre » cua te, cuu tre, dua tren
hanh de » hanh ve, hanh kem
sach ky » sach y, sach ty, sach kem
hieu ve » hieu va, hieu van
nang ma » tang ma, sang ma, nang cao
ma hoi » mai hoi, xa hoi, ma hoa
ve nam » he nam, va nam, le nam
sac ky » cac ky, sai ky

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 ky) or (sac ky)) nang ma hoi. hieu ve nam thuc vat hanh de ((cua tre) or (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach ky) OR (sac ky)) nang ma hoi. hieu ve nam thuc vat hanh de ((cua tre) OR (cua triet)).
• Adding a wildcard symbol may retrieve word variants: su ((sach ky) or (sac ky)) nang ma hoi. hieu ve nam thuc vat hanh de ((cua tre) or (cua triet))*.