Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
qua ban » cua ban, qua quan
duc ban » duc tan, duc van, dua ban
te sach » toc sach
hoi doi » hoi doai, hoc doi, hoa doi
hoi hoi » hoi hoc, hoc hoi, doi hoi
hieu ve » hieu va, hieu van
sach v » sach va, sach y, sach 2
ve cac » va cac, vien cac
v nang » va nang, vu nang, van nang
vi su » va su, ve su, ki su

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: te sach v nang ((hoi hoi) OR (hoi doi)). hieu ve cac ((duc ban) OR (qua ban)) hanh vi su triet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach v nang ((hoi hoi) OR (hoi doi)). hieu ve cac ((duc ban) or (qua ban)) hanh vi su triet~".
• Adding a wildcard symbol may retrieve word variants: te sach v nang ((hoi hoi) OR (hoi doi)). hieu ve cac ((duc ban) or (qua ban)) hanh vi su triet*.