Perhaps you should try some spelling variations:
cua triet » cua viet, su triet
toc sach » hoc sach, doc sach, thuoc sach
van tham » van thanh, van tuan, van chat
hanh dai » hanh tai, hanh dao, vanh dai
tham tuc » tham thuc, thai tuc, nham thuc
va triet » va thiet, va trien, ve triet
hieu van » hieu va, thien van, lieu va
nang mai » nang ma, nang tai, lang mai
va hanh » van hanh, va thanh, va danh
mai hoi » mai khoi, dai hoi, lai hoi
cua tre » cua te, cuu tre, dua tren
y nang » ky nang, ly nang, v nang
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: toc sach y nang mai hoi. hieu van tham tuc va hanh dai ((cua tre) or (((cua triet) OR (va triet))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach y nang mai hoi. hieu van tham tuc va hanh dai ((cua tre) OR (((cua triet) OR (va triet)))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach y nang mai hoi. hieu van tham tuc va hanh dai ((cua tre) or (((cua triet) OR (va triet))))".
• Adding a wildcard symbol may retrieve word variants: toc sach y nang mai hoi. hieu van tham tuc va hanh dai ((cua tre) or (((cua triet) OR (va triet))))*.