Perhaps you should try some spelling variations:
cham duc » pham duc, cham soc, pham duy
va hanh » van hanh, va thanh, va danh
tu cham » toc cham, thi cham
sach tu » sach thu, cach tu, sach ty
tu sach » thu sach, su sach, te sach
hieu tu » chieu tu, hieu tuc, hien tu
tu nang » tru nang, tu nong, tu nano
de cua » le cua, dieu cua
te cua » tue cua, le cua
o hoi » co hoi, o hoc, o hai
x hoi » xa hoi, x ho, 5 hoi

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