Perhaps you should try some spelling variations:
chau phu » chau phi, chau au, chau tho
vu sach » vu bach, su sach, vu khach
hanh ki » hanh vi, hanh ky, hanh kien
va hanh » van hanh, va thanh, va danh
cau luc » cau truc, cau phuc
sach ty » sach y, sach tu, sach thu
su viet » so viet
hieu ve » hieu va, hieu van
ty tang » tay tang, ty xang, ty hang
ma hoi » mai hoi, xa hoi, me hoi
ki su » ky su

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

• Performing a fuzzy search may retrieve terms with similar spellings: vu sach ty tang ((ma hoi) or (ma hoa)). hieu ve ((cau luc) or (chau phu)) va hanh ki su viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach ty tang ((ma hoi) OR (ma hoa)). hieu ve ((cau luc) OR (chau phu)) va hanh ki su viet.
• Adding a wildcard symbol may retrieve word variants: vu sach ty tang ((ma hoi) or (ma hoa)). hieu ve ((cau luc) or (chau phu)) va hanh ki su viet*.