Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
cua tre » cua te, cuu tre, cua triet
cac loc » cac lop, cac toc, cac hoc
lai cua » dai cua, hai cua, lai chau
va hanh » va thanh, va danh, ban hanh
hieu va » lieu va, hieu qua
xay hoi » xa hoi, tay hoi, cay phoi
ky danh » ky anh
ky dang » ky nang
tu sac » tu sach, tu cac, tu san

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sac ((ky dang) or (ky danh)) xay hoi. hieu va cac loc ((va hanh) OR (van hanh)) lai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sac ((ky dang) OR (ky danh)) xay hoi. hieu va cac loc ((va hanh) OR (van hanh)) lai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sac ((ky dang) or (ky danh)) xay hoi. hieu va cac loc ((va hanh) OR (van hanh)) lai cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sac ((ky dang) or (ky danh)) xay hoi. hieu va cac loc ((va hanh) OR (van hanh)) lai cua tre*.