Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
tu sach » thu sach, su sach, te sach
cao tuc » dao tuc, cao duc, cao suc
so sach » so sanh, bo sach, co sach
nang xa » nang x, lang xa, nang ma
hieu ve » hieu va
hanh va » hang va, hanh vi
va hanh » van hanh, va thanh, va danh
va cua » va chua, via cua, ca cua
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: ((tu sach) or (so sach)) ky nang xa hoi. ((hieu ve) OR (hieu van)) cao tuc va hanh va cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (so sach)) ky nang xa hoi. ((hieu ve) OR (hieu van)) cao tuc va hanh va cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (so sach)) ky nang xa hoi. ((hieu ve) OR (hieu van)) cao tuc va hanh va cua te".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (so sach)) ky nang xa hoi. ((hieu ve) OR (hieu van)) cao tuc va hanh va cua te*.