Perhaps you should try some spelling variations:
thanh vai » thanh hai, thanh van, thanh tai
va thanh » gia thanh, ban thanh, va tinh
hieu van » hieu va, thien van, lieu va
tu sach » thu sach, su sach, te sach
cao duc » dao duc, cao suc, giao duc
vai cua » dai cua, hai cua, lai cua
so sach » so sanh, bo sach, co sach
nang xa » nang x, lang xa, nang ma
hieu ve » hieu va
cua tu » cua tuc, cua su, cua cu

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 duc va thanh vai cua tu~.
• 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 duc va thanh vai cua tu.
• 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 duc va thanh vai cua tu".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (so sach)) ky nang xa hoi. ((hieu ve) OR (hieu van)) cao duc va thanh vai cua tu*.