Perhaps you should try some spelling variations:
cham hoc » cham soc, chat hoc, cham hoi
ky trong » ly trong, ke trong, cay trong
va danh » va dinh, va dan, va hanh
ve cham » va cham, ve chat, vu cham
hieu ve » hieu va, hieu van
ky dang » ky nang, ky danh
vi dau » vi dai, bi dau, ve dau
va dau » va dao
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 trong)) xa hoi. hieu ve cham hoc va danh ((vi dau) OR (va dau)) tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sac ((ky dang) OR (ky trong)) xa hoi. hieu ve cham hoc va danh ((vi dau) OR (va dau)) tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sac ((ky dang) or (ky trong)) xa hoi. hieu ve cham hoc va danh ((vi dau) OR (va dau)) tren".
• Adding a wildcard symbol may retrieve word variants: tu sac ((ky dang) or (ky trong)) xa hoi. hieu ve cham hoc va danh ((vi dau) OR (va dau)) tren*.