Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
cua triet » cua viet, su triet, va triet
hieu van » hieu va, thien van, lieu va
dau phuc » cau phuc, dieu phuc, dau khu
hanh dai » hanh tai, hanh dao, vanh dai
cao hoi » cau hoi, co hoi, cao hoc
van dau » van dao, phan dau
phuc va » phuc vu, thuc va, chuc va
va hanh » van hanh, va thanh, va danh
cuu tre » cua tre, cau tren, cau treo
y nang » ky nang, ly nang, v nang

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuoc sach y nang cao hoi. hieu van dau phuc va hanh dai ((cuu tre) or (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuoc sach y nang cao hoi. hieu van dau phuc va hanh dai ((cuu tre) OR (cua triet)).
• Adding a wildcard symbol may retrieve word variants: thuoc sach y nang cao hoi. hieu van dau phuc va hanh dai ((cuu tre) or (cua triet))*.