Perhaps you should try some spelling variations:
cua triet » cua viet, su triet
thanh vai » thanh hai, thanh van, thanh tai
cac nuoc » cap nuoc, hoc nuoc, dat nuoc
nuoc gia » nuoc giai, nuoc giao, quoc gia
va triet » va thiet, va trien, ve triet
te sach » toc sach
sach ky » sac ky, sach y, sach ty
nang ro » nang co, nang ho, nang ra
hieu va » lieu va, hieu qua
nang o » nang co, nang ho, nang x

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 ky ((nang o) OR (nang ro)) hoi. hieu va cac nuoc gia thanh vai ((cua triet) or (va triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky ((nang o) OR (nang ro)) hoi. hieu va cac nuoc gia thanh vai ((cua triet) OR (va triet))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky ((nang o) OR (nang ro)) hoi. hieu va cac nuoc gia thanh vai ((cua triet) or (va triet))*".