Perhaps you should try some spelling variations:
cua triet » cua viet, su triet
va thanh » gia thanh, ban thanh, va tinh
va triet » va thiet, va trien, ve triet
ky lang » ky nang, ky dang, ky tang
hieu va » lieu va, hieu qua
cac duc » cac du, cao duc, cac dac
su sac » su sach, su cac, su xac
sac ky » cac ky, sai ky
ha hoi » hoa hoi, xa hoi, va hoi

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sac ky lang ((ha hoi) or (ha noi)). hieu va cac duc va thanh san ((cua triet) OR (va triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sac ky lang ((ha hoi) OR (ha noi)). hieu va cac duc va thanh san ((cua triet) OR (va triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sac ky lang ((ha hoi) or (ha noi)). hieu va cac duc va thanh san ((cua triet) OR (va triet))".
• Adding a wildcard symbol may retrieve word variants: su sac ky lang ((ha hoi) or (ha noi)). hieu va cac duc va thanh san ((cua triet) OR (va triet))*.