Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
nam thuc » nam thuoc, am thuc, nam thu
thuc dan » thuc hanh, hoc dan, thuc vat
dan danh » van danh, han danh, ban danh
cau tren » cu tren, dau tren, ca tren
sach ky » sac ky, sach ty, sach kem
lang xa » lang ha, dang xay, lang van
danh vi » hanh vi, dinh vi, danh di
cua tre » cua te, cuu tre, cua triet

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((sach ky) or (sach y)) lang xa hoi. hieu van nam thuc dan danh vi ((cau tren) or (cua tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (sach y)) lang xa hoi. hieu van nam thuc dan danh vi ((cau tren) OR (cua tre)).
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) or (sach y)) lang xa hoi. hieu van nam thuc dan danh vi ((cau tren) or (cua tre))*.