Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
va thanh » gia thanh, ban thanh, va tinh
thanh vi » hanh vi, thanh va, thanh ve
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
ky mang » ky nang, ke mang, ky dang
may hoa » may khoa, ma hoa, day hoa
hieu ve » hieu van
hieu va » lieu va, hieu qua
cac duc » cac du, cao duc, cac dac
cua tre » cua te, cuu tre, dua tren

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