Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
thu sach » thuat sach, thuoc sach, thu hoach
va thanh » gia thanh, ban thanh, le thanh
cau duc » cao duc, cau luc, chu duc
va tinh » may tinh
tu sach » su sach, te sach, tu cach
nang o » nang co, nang ho, nang ro
lam su » lai su, lam so, lam vu
va cau » van cau, va cac, va dau
o hoi » co hoi, o hoc, o hai

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 (thu sach)) ky nang o hoi. lieu va cau duc ((va thanh) OR (va tinh)) lam su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu sach)) ky nang o hoi. lieu va cau duc ((va thanh) OR (va tinh)) lam su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (thu sach)) ky nang o hoi. lieu va cau duc ((va thanh) OR (va tinh)) lam su triet".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (thu sach)) ky nang o hoi. lieu va cau duc ((va thanh) OR (va tinh)) lam su triet*.