Perhaps you should try some spelling variations:
hieu cac » hieu luc, hieu va, hieu van
vien cac » vien bach, vien dai, vien da
hanh vai » hanh vi, hanh va, hanh tai
hien cac » thien cac, dien cac, bien cac
vai cua » dai cua, hai cua, lai cua
va hanh » van hanh, va thanh, va danh
su sach » so sach, vu sach
nang xa » nang x, lang xa, nang ma
sach ty » sach y, sach tu, sach thu
ty nang » ky nang, ty xang, ty hang
cua te » cua tu
lo va » lo van, lao va, ly va

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