Perhaps you should try some spelling variations:
hien cac » thien cac, vien cac, dien cac
hanh vai » hanh vi, hanh va, hanh tai
hieu cac » hieu luc, hieu va, hieu van
vai cua » dai cua, hai cua, lai cua
va hanh » van hanh, va thanh, va danh
sach ky » sac ky, sach y, sach ty
vu sach » vu bach, su sach, vu khach
nang xa » nang x, lang xa, mang xa
nang ma » tang ma, sang ma, nang cao
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: vu sach ky ((nang xa) or (nang ma)) hoi. hieu ((hien cac) OR (hieu cac)) lo va hanh vai cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach ky ((nang xa) OR (nang ma)) hoi. hieu ((hien cac) OR (hieu cac)) lo va hanh vai cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu sach ky ((nang xa) or (nang ma)) hoi. hieu ((hien cac) OR (hieu cac)) lo va hanh vai cua te".
• Adding a wildcard symbol may retrieve word variants: vu sach ky ((nang xa) or (nang ma)) hoi. hieu ((hien cac) OR (hieu cac)) lo va hanh vai cua te*.