Perhaps you should try some spelling variations:
cua triet » cua viet, su triet
va triet » va thiet, va trien, ve triet
dang xay » dang van, van xay
sach ky » sac ky, sach y, sach ty
hanh va » hang va, hanh vi
va hanh » van hanh, va thanh, va danh
tu sach » thu sach, su sach, te sach
hieu va » lieu va, hieu qua
hai tuc » thai tuc, hai cuc, thai thuc
va hai » van hai, va chai, va khai
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 x) or (dang xay)) hoi. hieu va hai tuc va hanh va ((cua triet) or (va triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky ((nang x) OR (dang xay)) hoi. hieu va hai tuc va hanh va ((cua triet) OR (va triet)).
• Adding a wildcard symbol may retrieve word variants: tu sach ky ((nang x) or (dang xay)) hoi. hieu va hai tuc va hanh va ((cua triet) or (va triet))*.