Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
hieu van » hieu va, thien van, lieu va
cham duc » pham duc, cham soc, pham duy
van hanh » van thanh, ban hanh, van anh
nang xa » nang x, lang xa, nang ma
hieu ve » hieu va
va hanh » va thanh, va danh, ban hanh
sach v » sach va, sach y, sach 2
v nang » va nang, vu nang, van nang
du hoa » duc hoa, do hoa, du hoc

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

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