Perhaps you should try some spelling variations:
van khanh » van thanh, van hanh, van anh
vien cac » vien bach, vien dai, vien da
khanh di » khanh bui, khanh duy, thanh doi
truc van » truc va, thuc van, truc ban
su triet » su viet, su tien, ve triet
va nang » van nang, da nang, cam nang
su sach » so sach, vu sach
v nang » vu nang, van nang, voi nang
x hoi » xa hoi, o hoi, x ho
di su » doi su, ki su, da su
hien » bien, tien, dien

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: su sach ((v nang) OR (va nang)) x hoi. hieu ((vien cac) OR (hien dai)) truc van khanh di su triet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ((v nang) OR (va nang)) x hoi. hieu ((vien cac) or (hien dai)) truc van khanh di su triet~".
• Adding a wildcard symbol may retrieve word variants: su sach ((v nang) OR (va nang)) x hoi. hieu ((vien cac) or (hien dai)) truc van khanh di su triet*.