Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
hanh va » hang va, hanh vi
qua ban » cua ban, qua quan
duc ban » duc tan, duc van, dua ban
tu sach » thu sach, su sach, te sach
hieu ve » hieu va, hieu van
sach 2 » sach y
2 nang » v nang
ve cac » va cac, vien cac
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 2 nang ((x hoi) OR (o hoi)). hieu ve cac ((duc ban) or (qua ban)) hanh va su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach 2 nang ((x hoi) OR (o hoi)). hieu ve cac ((duc ban) OR (qua ban)) hanh va su triet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach 2 nang ((x hoi) OR (o hoi)). hieu ve cac ((duc ban) or (qua ban)) hanh va su triet*".