Perhaps you should try some spelling variations:
hanh vai » hanh vi, hanh va, hanh tai
te sach » toc sach
sach tu » sach thu, cach tu, sach ty
nang xa » lang xa, nang ma, mang xa
hieu ve » hieu va, hieu van
duc van » duc tan, duc manh, duc phan
vai cua » dai cua, hai cua, lai cua
ve cac » va cac, vien cac
cua tu » cua tuc, cua su, cua cu

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

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