Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, hieu ve
cuu thuc » cuu tac
thuc dan » thuc hanh, hoc dan, thuc vat
dan hanh » dang hanh, dan khanh, dan thanh
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
nang xa » lang xa, nang ma, mang xa
hanh de » hanh ve, hanh kem
de cua » le cua, te cua, dieu cua
cua tu » cua tuc, cua su, cua cu

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 ((nang xa) or (nang x)) hoi. ((hieu van) or (lieu va)) cuu thuc dan hanh de cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky ((nang xa) OR (nang x)) hoi. ((hieu van) OR (lieu va)) cuu thuc dan hanh de cua tu.
• Adding a wildcard symbol may retrieve word variants: tu sach ky ((nang xa) or (nang x)) hoi. ((hieu van) or (lieu va)) cuu thuc dan hanh de cua tu*.