Perhaps you should try some spelling variations:
hanh lai » hanh lam, hanh tai, thanh lap
van hanh » van thanh, ban hanh, van anh
sach thu » sach thue, sach thieu, sach tham
cham duc » pham duc, cham soc, pham duy
van cham » van chat, van tham, va cham
hieu van » hieu va, thien van, lieu va
duc van » duc va, duc tan, duc manh
ca viet » va viet, co viet, hoa viet
sach ty » sach y, sach tu, xach tay
lai ca » lai cua, lai cam, loai ca
x hoi » xa hoi, x ho, 5 hoi
o hoi » co hoi, o hoc, o hai

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 ty) OR (sach thu)) nang ((x hoi) or (o hoi)). hieu van cham duc van hanh lai ca viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ty) OR (sach thu)) nang ((x hoi) OR (o hoi)). hieu van cham duc van hanh lai ca viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ty) OR (sach thu)) nang ((x hoi) or (o hoi)). hieu van cham duc van hanh lai ca viet".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ty) OR (sach thu)) nang ((x hoi) or (o hoi)). hieu van cham duc van hanh lai ca viet*.