Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
tu sach » thu sach, su sach, te sach
cua tre » cua te, cua triet, dua tren
danh vi » hanh vi, dinh vi, danh di
va danh » va dinh, va dan, va hanh
sach ky » sac ky, sach y, sach ty
cau tuc » cau truc, cau tu, cau luc
van cau » van dau, van hau, van chat
lang xa » lang ha, dang xay, lang van
nang xa » nang x, nang ma, mang xa
cuu tre » cau tren, cau treo
tuc va » thuc va, truc va, tuc xa

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 (lang xa)) hoi. hieu van cau tuc va danh vi ((cua tre) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky ((nang xa) OR (lang xa)) hoi. hieu van cau tuc va danh vi ((cua tre) OR (cuu tre)).
• Adding a wildcard symbol may retrieve word variants: tu sach ky ((nang xa) or (lang xa)) hoi. hieu van cau tuc va danh vi ((cua tre) or (cuu tre))*.