Perhaps you should try some spelling variations:
van triet » va triet, van thiet, van trieu
hoc sach » hoc sinh, hoc cac, hoc anh
vien cac » vien bach, vien dai, gian cac
ty hang » ly hang, ty xang, thi hang
vien da » vien dai, hien dai
va hanh » van hanh, va thanh, va danh
hanh ve » hanh vi, hanh va, hanh kem
ty nang » ky nang, ty xang, ly nang
ve van » le van
x hoi » xa hoi, o hoi, x ho

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: hoc sach ((ty nang) or (ty hang)) x hoi. hieu ((vien cac) OR (vien da)) duc va hanh ve van triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc sach ((ty nang) OR (ty hang)) x hoi. hieu ((vien cac) OR (vien da)) duc va hanh ve van triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc sach ((ty nang) or (ty hang)) x hoi. hieu ((vien cac) OR (vien da)) duc va hanh ve van triet".
• Adding a wildcard symbol may retrieve word variants: hoc sach ((ty nang) or (ty hang)) x hoi. hieu ((vien cac) OR (vien da)) duc va hanh ve van triet*.