Perhaps you should try some spelling variations:
van thang » van thanh, van khang, van hang
kho tang » cao tang
luc van » luoc van, luu van, duc van
hai cuc » tai cuc, hai cua, thai cua
hai cuu » hai cua, hai chu, thai cua
cac luc » cau luc, coc luc, cac nuoc
ky tang » ky nang, ky dang, ky trong
qua cac » cua cac
su cac » tu cac, su cao, su can

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

• Performing a fuzzy search may retrieve terms with similar spellings: su cac ((ky tang) or (kho tang)) xa hoi. hieu qua cac luc van thang ((hai cuu) OR (hai cuc)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su cac ((ky tang) OR (kho tang)) xa hoi. hieu qua cac luc van thang ((hai cuu) OR (hai cuc)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su cac ((ky tang) or (kho tang)) xa hoi. hieu qua cac luc van thang ((hai cuu) OR (hai cuc)) tre".
• Adding a wildcard symbol may retrieve word variants: su cac ((ky tang) or (kho tang)) xa hoi. hieu qua cac luc van thang ((hai cuu) OR (hai cuc)) tre*.