Perhaps you should try some spelling variations:
va thieu » va thiet, va hieu, va tieu
han thai » han tai, ban thai, van thai
cham duc » pham duc, cham soc, pham duy
thai va » thai van
ve cham » va cham, ve chat, vu cham
hieu ve » hieu va, hieu van
so sach » bo sach, co sach, hoc sach
nang xa » lang xa, nang ma, mang xa
so sanh » do sanh
va han » va phan, van han, va hanh

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

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