Perhaps you should try some spelling variations:
hieu vien » hieu hien, hieu viec, thieu nien
vien cac » vien bach, vien dai, vien da
so sanh » do sanh
tu manh » tu minh, tu hanh, vu manh
manh xa » manh xay, mang xa, manh ba
sanh tu » anh tu, danh tu, hanh tu
cua tre » cuu tre, cua triet, dua tren
xac va » tac va, ac va, bac va
tuc va » thuc va, truc va, tuc xa
cua te » cua tu

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sanh tu manh xa hoi. hieu vien cac ((xac va) or (tuc va)) hanh vi ((cua tre) OR (cua te))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sanh tu manh xa hoi. hieu vien cac ((xac va) OR (tuc va)) hanh vi ((cua tre) OR (cua te)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sanh tu manh xa hoi. hieu vien cac ((xac va) or (tuc va)) hanh vi ((cua tre) OR (cua te))".
• Adding a wildcard symbol may retrieve word variants: so sanh tu manh xa hoi. hieu vien cac ((xac va) or (tuc va)) hanh vi ((cua tre) OR (cua te))*.