Perhaps you should try some spelling variations:
pham thuc » phap thuc, pham chuc, nham thuc
su triet » su viet, su tien
hanh van » thanh van, khanh van, hanh va
doc sach » hoc sach, toc sach, nuoc sach
ve triet » va trien
hieu ve » hieu va, hieu van
ve pham » vi pham, v pham, ve phan
sach ky » sac ky, sach y, sach ty
thuc va » thuc vat, thuc dan, thuc day
va hanh » van hanh, va thanh, va danh
cao hoi » co hoi, cao hoc, tao hoi

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

• Performing a fuzzy search may retrieve terms with similar spellings: doc sach ky nang ((cao hoi) or (cau hoi)). hieu ve pham thuc va hanh van ((su triet) OR (ve triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc sach ky nang ((cao hoi) OR (cau hoi)). hieu ve pham thuc va hanh van ((su triet) OR (ve triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc sach ky nang ((cao hoi) or (cau hoi)). hieu ve pham thuc va hanh van ((su triet) OR (ve triet))".
• Adding a wildcard symbol may retrieve word variants: doc sach ky nang ((cao hoi) or (cau hoi)). hieu ve pham thuc va hanh van ((su triet) OR (ve triet))*.