Perhaps you should try some spelling variations:
hanh cham » thanh cham, thanh pham, khanh pham
qua cham » qua hai, qua cac, va cham
cham luc » cham soc, nhan luc, cham cuu
cham cua » chat cua, cham cuu, ham cua
cua viet » ca viet, hoa viet, cua vat
su sach » so sach, vu sach
sach tu » sach thu, cach tu, sach ty
tu nang » tru nang, tu nong, tu nano
mai hoi » mai khoi, dai hoi, lai hoi
va hanh » van hanh, va thanh, va danh
ma hoi » xa hoi, ma hoa, me hoi
luc va » duc va, tuc va, loc va

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach tu nang ((ma hoi) or (mai hoi)). hieu qua cham luc va hanh cham cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach tu nang ((ma hoi) OR (mai hoi)). hieu qua cham luc va hanh cham cua viet.
• Adding a wildcard symbol may retrieve word variants: su sach tu nang ((ma hoi) or (mai hoi)). hieu qua cham luc va hanh cham cua viet*.