Perhaps you should try some spelling variations:
thieu nien » thien nhien
nien cac » vien cac, dien cac, bien cac
cua viet » ca viet, hoa viet, cua vat
tang ma » mang may, tang van
nang ma » sang ma, nang cao, mang may
sach ty » sach y, sach tu, sach thu
te sach » toc sach
xuc va » duc va, luc va, xac va
tuc va » thuc va, truc va, tuc xa
vi cua » vai cua, di cua

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 ty ((nang ma) OR (tang ma)) hoi. thieu nien cac ((xuc va) or (tuc va)) hanh vi cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ty ((nang ma) OR (tang ma)) hoi. thieu nien cac ((xuc va) OR (tuc va)) hanh vi cua viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ty ((nang ma) OR (tang ma)) hoi. thieu nien cac ((xuc va) or (tuc va)) hanh vi cua viet".
• Adding a wildcard symbol may retrieve word variants: te sach ty ((nang ma) OR (tang ma)) hoi. thieu nien cac ((xuc va) or (tuc va)) hanh vi cua viet*.