Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
vien dai » hien dai
van hanh » van thanh, ban hanh, van anh
truc van » truc va, thuc van, truc ban
vien cac » vien bach, vien da, gian cac
hanh di » hanh vi, hanh de, hang di
sach v » sach va, sach 2, sach vay
x hoi » xa hoi, o hoi, x ho
di su » doi su, ki su, da su

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 v) OR (sach y)) nang x hoi. hieu ((vien cac) or (vien dai)) truc van hanh di su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach v) OR (sach y)) nang x hoi. hieu ((vien cac) OR (vien dai)) truc van hanh di su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach v) OR (sach y)) nang x hoi. hieu ((vien cac) or (vien dai)) truc van hanh di su triet".
• Adding a wildcard symbol may retrieve word variants: su ((sach v) OR (sach y)) nang x hoi. hieu ((vien cac) or (vien dai)) truc van hanh di su triet*.