Perhaps you should try some spelling variations:
cua triet » cua viet, va triet
manh hanh » xanh hanh, danh thanh, minh thanh
hieu van » hieu va, thien van, lieu va
hanh via » hanh vi, hanh va, anh va
su triet » su viet, su tien, ve triet
so sach » so sanh, bo sach, co sach
nam suc » nam suu, nam soc, nam sach

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sach ((ty xang) or (ky nang)) xa hoi. hieu van nam suc manh hanh via ((cua triet) OR (su triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ((ty xang) OR (ky nang)) xa hoi. hieu van nam suc manh hanh via ((cua triet) OR (su triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach ((ty xang) or (ky nang)) xa hoi. hieu van nam suc manh hanh via ((cua triet) OR (su triet))".
• Adding a wildcard symbol may retrieve word variants: so sach ((ty xang) or (ky nang)) xa hoi. hieu van nam suc manh hanh via ((cua triet) OR (su triet))*.