Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
thanh ha » thanh hoa, thanh hai, nhanh ha
thu sach » tu sach, thuat sach, thuoc sach
thanh va » thanh van, hanh va, thanh ve
cac tac » cac toc, cac bac, cac dac
tu cach » tu cac
hieu ve » hieu va, hieu van
ty nang » ky nang, ty xang, ty hang
tac va » tac da, tac xa, tuc va
nang o » nang co, nang ho, nang ro
ve cac » va cac, vien cac
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 cach) or (thu sach)) ty nang o hoi. hieu ve cac tac va ((thanh va) OR (thanh ha)) su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu cach) OR (thu sach)) ty nang o hoi. hieu ve cac tac va ((thanh va) OR (thanh ha)) su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu cach) or (thu sach)) ty nang o hoi. hieu ve cac tac va ((thanh va) OR (thanh ha)) su triet".
• Adding a wildcard symbol may retrieve word variants: ((tu cach) or (thu sach)) ty nang o hoi. hieu ve cac tac va ((thanh va) OR (thanh ha)) su triet*.