Perhaps you should try some spelling variations:
thieu nien » thien nhien
nien cac » vien cac, dien cac, bien cac
van hanh » van thanh, ban hanh, van anh
su sach » so sach, vu sach
va hanh » va thanh, va danh, ban hanh
vai cua » dai cua, hai cua, lai cua
y nang » ly nang, v nang, may nang
cac lo » cac lop, cac co, cac bo
cua te » cua tu

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 ((y nang) OR (ky nang)) xa hoi. thieu nien cac lo ((va hanh) or (van hanh)) vai cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ((y nang) OR (ky nang)) xa hoi. thieu nien cac lo ((va hanh) OR (van hanh)) vai cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ((y nang) OR (ky nang)) xa hoi. thieu nien cac lo ((va hanh) or (van hanh)) vai cua te".
• Adding a wildcard symbol may retrieve word variants: su sach ((y nang) OR (ky nang)) xa hoi. thieu nien cac lo ((va hanh) or (van hanh)) vai cua te*.