Perhaps you should try some spelling variations:
thuc nguoi » toc nguoi
nguoi san » nguoi tay, nguoi dao, nguoi ma
cua triet » cua viet, su triet, va triet
san hanh » san thanh, ban hanh, van hanh
hieu le » hieu ve, hieu he, hieu ly
le thuc » le tuc, le thuy, ve thuc
cua tre » cua te, cuu tre, dua tren
su sai » su tai, su hai, su dai
sai ky » sac ky
nang o » nang co, nang ho, nang ro
cua tu » cua tuc, cua su, cua cu
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: su sai ky nang o hoi. hieu le thuc nguoi san hanh vi ((((cua tre) OR (cua triet))) or (cua tu))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sai ky nang o hoi. hieu le thuc nguoi san hanh vi ((((cua tre) OR (cua triet))) OR (cua tu))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sai ky nang o hoi. hieu le thuc nguoi san hanh vi ((((cua tre) OR (cua triet))) or (cua tu))*".