Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
cua triet » cua viet, su triet, va triet
hieu van » hieu va, thien van, lieu va
van pham » san pham, van phan, van phat
pham huu » pham duc, pham duy, phan huy
dinh dai » dinh dat, sinh dai, dinh dao
sach ky » sac ky, sach y, sach ty
nang xa » lang xa, nang ma, mang xa
va dinh » van dinh, va kinh, va tinh
cua tre » cua te, cuu tre, dua tren
huu va » cuu va, tuu va

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuat sach ky ((nang xa) or (nang x)) hoi. hieu van pham huu va dinh dai ((cua tre) or (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuat sach ky ((nang xa) OR (nang x)) hoi. hieu van pham huu va dinh dai ((cua tre) OR (cua triet)).
• Adding a wildcard symbol may retrieve word variants: thuat sach ky ((nang xa) or (nang x)) hoi. hieu van pham huu va dinh dai ((cua tre) or (cua triet))*.