Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
sach thi » sach thu, sach tai, sach thieu
va triet » va thiet, va trien, ve triet
hanh vai » hanh vi, hanh va, hanh tai
cac nuoc » cap nuoc, hoc nuoc, dat nuoc
su triet » su viet, su tien, ve triet
thi hanh » thi thanh
hieu va » lieu va, hieu qua
cac toc » cac toi, cac thoi
xa hanh » xa thanh, xa khanh, va hanh
hanh ca » hanh cac, hanh cat, hanh cua
ca hoi » cau hoi, cua hoi, xa hoi

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach thi hanh ca hoi. hieu va ((cac toc) or (cac nuoc)) xa hanh vai ((va triet) or (su triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach thi hanh ca hoi. hieu va ((cac toc) OR (cac nuoc)) xa hanh vai ((va triet) OR (su triet)).
• Adding a wildcard symbol may retrieve word variants: toc sach thi hanh ca hoi. hieu va ((cac toc) or (cac nuoc)) xa hanh vai ((va triet) or (su triet))*.