Perhaps you should try some spelling variations:
va thanh » gia thanh, ban thanh, va tinh
thanh va » thanh van, hanh va, thanh ha
su triet » su viet, su tien
ve triet » va trien
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
cao hoi » cau hoi, co hoi, cao hoc
hieu va » hieu qua
thu va » thuc va, thue va, tu va

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

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