Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
hieu van » hieu va, thien van, lieu va
va thanh » gia thanh, ban thanh, va tinh
va danh » va dinh, va dan, va hanh
sach ky » sac ky, sach y, sach ty
su sach » so sach, vu sach
ky tang » ky nang, ky dang, kho tang
van cau » van dau, van hau, van chat
cau tu » dau tu, cau truc
ma hoi » mai hoi, xa hoi, me hoi
vi su » va su, ve su, ki su

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 tang ((ma hoi) OR (ma hoa)). hieu van cau tu ((va thanh) or (va danh)) vi su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky tang ((ma hoi) OR (ma hoa)). hieu van cau tu ((va thanh) OR (va danh)) vi su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky tang ((ma hoi) OR (ma hoa)). hieu van cau tu ((va thanh) or (va danh)) vi su triet".
• Adding a wildcard symbol may retrieve word variants: su sach ky tang ((ma hoi) OR (ma hoa)). hieu van cau tu ((va thanh) or (va danh)) vi su triet*.