Perhaps you should try some spelling variations:
te sach » toc sach
sach tu » sach thu, cach tu, sach ty
nang xa » nang x, lang xa, mang xa
nang ma » tang ma, sang ma, nang cao
hieu ve » hieu va, hieu van
duc van » duc tan, duc manh, duc phan
ve cac » va cac, vien cac
vi cua » vai cua, di cua
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 ma)) hoi. hieu ve cac ((duc van) or (duc va)) hanh vi cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach tu ((nang xa) OR (nang ma)) hoi. hieu ve cac ((duc van) OR (duc va)) hanh vi cua tu.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach tu ((nang xa) OR (nang ma)) hoi. hieu ve cac ((duc van) or (duc va)) hanh vi cua tu".
• Adding a wildcard symbol may retrieve word variants: te sach tu ((nang xa) OR (nang ma)) hoi. hieu ve cac ((duc van) or (duc va)) hanh vi cua tu*.