Perhaps you should try some spelling variations:
cua triet » su triet, va triet
truc van » thuc van, truc ban, truc dan
cua viet » ca viet, hoa viet, cua vat
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
truc va » thuc va, thuc vat, trung va
hanh va » hang va, hanh vi
nang o » nang co, nang ho, nang ro
va nam » van nam, ha nam, va nay
o hai » co hai, so hai, o lai

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: tu sach ky nang o hai. lieu va nam ((truc van) OR (truc va)) hanh va ((cua triet) OR (cua viet))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang o hai. lieu va nam ((truc van) OR (truc va)) hanh va ((cua triet) or (cua viet))~".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang o hai. lieu va nam ((truc van) OR (truc va)) hanh va ((cua triet) or (cua viet))*.