Perhaps you should try some spelling variations:
cua triet » cua viet, va triet
su triet » su viet, su tien, ve triet
cac nuoc » cap nuoc, hoc nuoc, dat nuoc
hang vi » hang va, hanh vi, hang di
va hang » van hang, va nang, va lang
te sach » toc sach
hieu ve » hieu va, hieu van
ly nang » ky nang, ly hang, ly vang
y nang » ky nang, v nang, may nang
ve cac » va cac, vien cac

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ((y nang) OR (ly nang)) ma hoa. hieu ve cac nuoc va hang vi ((cua triet) or (su triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ((y nang) OR (ly nang)) ma hoa. hieu ve cac nuoc va hang vi ((cua triet) OR (su triet))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ((y nang) OR (ly nang)) ma hoa. hieu ve cac nuoc va hang vi ((cua triet) or (su triet))*".