Perhaps you should try some spelling variations:
danh dien » danh kien, danh lien, nganh dien
dinh dien » tinh dien, kinh dien, dich dien
thu sach » tu sach, thuat sach, thuoc sach
hieu van » hieu va, thien van, lieu va
dau truc » cau truc, dai truc, doan truc
sach ky » sac ky, sach y, sach ty
truc va » thuc va, thuc vat, trung va
van dau » van dao, phan dau
nang xa » nang x, lang xa, nang ma
cuu tre » cua tre, cau tren, cau treo
cu tre » cu tren, cua tre, cu tri

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach ky nang xa hoi. hieu van dau truc va ((danh dien) OR (dinh dien)) ((cu tre) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ky nang xa hoi. hieu van dau truc va ((danh dien) OR (dinh dien)) ((cu tre) OR (cuu tre)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ky nang xa hoi. hieu van dau truc va ((danh dien) OR (dinh dien)) ((cu tre) or (cuu tre))".
• Adding a wildcard symbol may retrieve word variants: thu sach ky nang xa hoi. hieu van dau truc va ((danh dien) OR (dinh dien)) ((cu tre) or (cuu tre))*.