Perhaps you should try some spelling variations:
thuc van » thuc vat, thuc dan, thuc va
hanh dao » lanh dao, thanh dat, thanh dam
hanh dai » hanh tai, vanh dai, thanh dat
cua tre » cua te, cuu tre, cua triet
hieu ve » hieu va, hieu van
nang ma » tang ma, sang ma, nang cao
ma hoi » mai hoi, xa hoi, ma hoa
sac ky » cac ky, sai ky
ve am » va am

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 y) or (sac ky)) nang ma hoi. hieu ve am thuc van ((hanh dai) OR (hanh dao)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach y) OR (sac ky)) nang ma hoi. hieu ve am thuc van ((hanh dai) OR (hanh dao)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach y) or (sac ky)) nang ma hoi. hieu ve am thuc van ((hanh dai) OR (hanh dao)) cua tre".
• Adding a wildcard symbol may retrieve word variants: su ((sach y) or (sac ky)) nang ma hoi. hieu ve am thuc van ((hanh dai) OR (hanh dao)) cua tre*.