Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
su sach » vu sach
so sach » so sanh, bo sach, co sach
nang xa » lang xa, nang ma, mang xa
hieu va » lieu va, hieu qua
cac thu » cach thuc, cac thoi
va kinh » va tinh, qua kinh
kinh va » kinh van, tinh va, sinh va
thu va » thuc va, thue va, tu va

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: ((su sach) OR (so sach)) ky ((nang xa) OR (nang x)) hoi. hieu va cac thu va kinh va su triet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su sach) OR (so sach)) ky ((nang xa) or (nang x)) hoi. hieu va cac thu va kinh va su triet~".
• Adding a wildcard symbol may retrieve word variants: ((su sach) OR (so sach)) ky ((nang xa) or (nang x)) hoi. hieu va cac thu va kinh va su triet*.