Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
hieu van » hieu va, thien van, lieu va
chat cua » nhat cua, chat va, chat huu
kinh dai » sinh dai, kinh dao, kinh hai
sach ky » sac ky, sach y, sach ty
nang xa » lang xa, nang ma, mang xa
va kinh » va tinh, qua kinh
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: thuat sach ky ((nang xa) or (nang x)) hoi. hieu van ((chat cua) or (cam xuc)) va kinh dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuat sach ky ((nang xa) OR (nang x)) hoi. hieu van ((chat cua) OR (cam xuc)) va kinh dai cua tre.
• Adding a wildcard symbol may retrieve word variants: thuat sach ky ((nang xa) or (nang x)) hoi. hieu van ((chat cua) or (cam xuc)) va kinh dai cua tre*.