Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
hieu van » hieu va, thien van, lieu va
nam thuc » nam thuoc, am thuc, nam thu
vat hanh » vat thanh, van hanh, va hanh
hanh via » hanh vi, hanh va, anh va
su sach » so sach, vu sach
nang ma » tang ma, sang ma, nang cao
via cua » gia cua, gian cua, giau cua
ma hoi » mai hoi, xa hoi, ma hoa

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

• If you are trying to use Boolean operators, they must be ALL CAPS: ((((tu cach) OR (tu cac))) OR (su sach)) ky nang ma hoi. hieu van nam thuc vat hanh via cua triet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((tu cach) OR (tu cac))) or (su sach)) ky nang ma hoi. hieu van nam thuc vat hanh via cua triet~".
• Adding a wildcard symbol may retrieve word variants: ((((tu cach) OR (tu cac))) or (su sach)) ky nang ma hoi. hieu van nam thuc vat hanh via cua triet*.