Perhaps you should try some spelling variations:
cua triet » cua viet, va triet
toc sach » hoc sach, doc sach, thuoc sach
van hang » van khang, van hoang, van thang
luoc van » luoc can, luoc va, luc van
su triet » su viet, su tien, ve triet
sach ky » sac ky, sach y, sach ty
nang ma » tang ma, sang ma, nang cao
ve hoc » te hoc, va hoc, de hoc
vi hoc » li hoc, va hoc

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 ky nang ma hoa. hieu ((ve hoc) OR (vi hoc)) luoc van hang va ((cua triet) or (su triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ky nang ma hoa. hieu ((ve hoc) OR (vi hoc)) luoc van hang va ((cua triet) OR (su triet))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ky nang ma hoa. hieu ((ve hoc) OR (vi hoc)) luoc van hang va ((cua triet) or (su triet))*".