Perhaps you should try some spelling variations:
danh lien » danh kien, doanh tien, doanh vien
danh dien » dinh dien, danh kien, nganh dien
dau truc » cau truc, dai truc, doan truc
hieu van » hieu va, thien van, lieu va
truc va » thuc va, thuc vat, trung va
te sach » toc sach
sach ky » sac ky, sach y, sach ty
van dau » van dao, phan dau
lang xa » lang ha, dang xay, lang van
nang xa » nang x, nang ma, mang xa
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: te sach ky ((nang xa) or (lang xa)) hoi. hieu van dau truc va ((danh dien) OR (danh lien)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky ((nang xa) OR (lang xa)) hoi. hieu van dau truc va ((danh dien) OR (danh lien)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky ((nang xa) or (lang xa)) hoi. hieu van dau truc va ((danh dien) OR (danh lien)) cua tre".
• Adding a wildcard symbol may retrieve word variants: te sach ky ((nang xa) or (lang xa)) hoi. hieu van dau truc va ((danh dien) OR (danh lien)) cua tre*.