Perhaps you should try some spelling variations:
khoa viet » khoan viet, hoa viet, thoai viet
thanh voi » thanh loi, thanh moi, hanh voi
van thanh » ban thanh, van tuan
voi khoa » noi khoa, hoi khoa, loi khoa
nang mai » nang ma, nang tai, lang mai
hieu va » lieu va, hieu qua
mai hoi » mai khoi, dai hoi, lai hoi
hieu ve » hieu van
xuc van » duc van, luc van, vuc van
cac xuc » cam xuc, cac nuoc, chat xuc
su cac » tu cac, su cao, eu cac
su can » su van, su cao, tu 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) OR (su can)) ky nang mai hoi. ((hieu ve) or (hieu va)) cac xuc van thanh voi khoa viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su cac) OR (su can)) ky nang mai hoi. ((hieu ve) OR (hieu va)) cac xuc van thanh voi khoa viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su cac) OR (su can)) ky nang mai hoi. ((hieu ve) or (hieu va)) cac xuc van thanh voi khoa viet".
• Adding a wildcard symbol may retrieve word variants: ((su cac) OR (su can)) ky nang mai hoi. ((hieu ve) or (hieu va)) cac xuc van thanh voi khoa viet*.