Perhaps you should try some spelling variations:
vai trien » va trien, cai thien, cai tien
nang dai » nang dau, nang tai, lang dai
hieu van » hieu va, thien van, lieu va
van hau » van ha, van hai, van dau
hau luc » hau loc, cau luc, nhan luc
va hanh » van hanh, va thanh, ban hanh
hanh va » hang va, hanh vi
xac ky » cac ky, bac ky
sac ky » cac ky, sai ky
luc va » duc va, tuc va, loc va
va vai » va bai, va van, va dai

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

• Performing a fuzzy search may retrieve terms with similar spellings: su ((xac ky) OR (sac ky)) nang dai hoc. hieu van hau luc va hanh va vai trien~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((xac ky) OR (sac ky)) nang dai hoc. hieu van hau luc va hanh va vai trien".
• Adding a wildcard symbol may retrieve word variants: su ((xac ky) OR (sac ky)) nang dai hoc. hieu van hau luc va hanh va vai trien*.