Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
hanh ki » hanh vi, hanh ky, hanh kien
qua ban » cua ban, qua quan
duc ban » duc tan, duc van, dua ban
hieu ve » hieu va, hieu van
nang xa » nang x, lang xa, nang ma
sach v » sach va, sach y, sach vay
sach 2 » sach y
ve cac » va cac, vien cac
ki su » ky 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: tu ((sach v) OR (sach 2)) nang xa hoi. hieu ve cac ((duc ban) OR (qua ban)) hanh ki su triet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach v) OR (sach 2)) nang xa hoi. hieu ve cac ((duc ban) or (qua ban)) hanh ki su triet~".
• Adding a wildcard symbol may retrieve word variants: tu ((sach v) OR (sach 2)) nang xa hoi. hieu ve cac ((duc ban) or (qua ban)) hanh ki su triet*.