Perhaps you should try some spelling variations:
hieu vien » hieu hien, hieu viec, thieu nien
vien cac » vien bach, vien dai, vien da
thai cua » than cua, tai cuc, dai cua
van hanh » van thanh, ban hanh, van anh
xuc van » duc van, luc van, vuc van
cac xuc » cam xuc, cac nuoc, chat xuc
tu sac » tu sach, tu cac, tu bac
nang o » nang co, nang ho, nang ro
tu san » thu san, tu ban, tu can
o lai » o lao

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) or (tu san)) ky nang o lai. hieu vien cac xuc van hanh ((thai cua) OR (tri cua)) te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sac) OR (tu san)) ky nang o lai. hieu vien cac xuc van hanh ((thai cua) OR (tri cua)) te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sac) or (tu san)) ky nang o lai. hieu vien cac xuc van hanh ((thai cua) OR (tri cua)) te".
• Adding a wildcard symbol may retrieve word variants: ((tu sac) or (tu san)) ky nang o lai. hieu vien cac xuc van hanh ((thai cua) OR (tri cua)) te*.