Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
sach van » sach han, sach va, bach van
van nang » van quang, van ban, van dong
ban hanh » ban hang
truc ban » thuc ban, truc dan, truc van
cua tre » cua te, cuu tre, dua tren
hanh de » hanh ve, hanh kem
su sach » so sach, vu sach
ve cac » va cac, vien cac
ve cam » ve cham, va cam, ve cai
nang o » nang co, nang ho, nang ro
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: su sach van nang o hoi. hieu ((ve cam) OR (ve cac)) truc ban hanh de ((cua tre) or (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach van nang o hoi. hieu ((ve cam) OR (ve cac)) truc ban hanh de ((cua tre) OR (cua triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach van nang o hoi. hieu ((ve cam) OR (ve cac)) truc ban hanh de ((cua tre) or (cua triet))".
• Adding a wildcard symbol may retrieve word variants: su sach van nang o hoi. hieu ((ve cam) OR (ve cac)) truc ban hanh de ((cua tre) or (cua triet))*.