Perhaps you should try some spelling variations:
khoa viet » khoan viet, hoa viet, thoai viet
ban thanh » ban hanh, ban hang
van thanh » van tuan
voi khoa » noi khoa, hoi khoa, loi khoa
nang dai » nang dau, nang tai, lang dai
ve cham » va cham, ve chat, vu cham
dai hoi » dai hoc, dai hai, dai moi
ve cam » ve cac, va cam, ve cai
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 nang dai hoi. hieu ((ve cam) OR (ve cham)) xuc ((van thanh) or (ban thanh)) voi khoa viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su cac ky nang dai hoi. hieu ((ve cam) OR (ve cham)) xuc ((van thanh) OR (ban thanh)) voi khoa viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su cac ky nang dai hoi. hieu ((ve cam) OR (ve cham)) xuc ((van thanh) or (ban thanh)) voi khoa viet".
• Adding a wildcard symbol may retrieve word variants: su cac ky nang dai hoi. hieu ((ve cam) OR (ve cham)) xuc ((van thanh) or (ban thanh)) voi khoa viet*.