Perhaps you should try some spelling variations:
cham hoc » cham soc, chat hoc, cham hoi
ky dang » ky nang, ky danh
ky tang » ky nang, kho tang, ky trong
hieu vu » hieu va, hieu ve, hieu su
vu cham » va cham, vu kham, tu cham
danh vi » dinh vi, danh di, danh va
cuu tre » cua tre, cau tren, cau treo
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 tang)) xa hoi. hieu vu cham hoc va ((danh vi) OR (hanh vi)) cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sac ((ky dang) OR (ky tang)) xa hoi. hieu vu cham hoc va ((danh vi) OR (hanh vi)) cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sac ((ky dang) or (ky tang)) xa hoi. hieu vu cham hoc va ((danh vi) OR (hanh vi)) cuu tre".
• Adding a wildcard symbol may retrieve word variants: tu sac ((ky dang) or (ky tang)) xa hoi. hieu vu cham hoc va ((danh vi) OR (hanh vi)) cuu tre*.