Perhaps you should try some spelling variations:
hanh thai » nhanh thai, hinh thai, hanh tai
van hanh » van thanh, ban hanh, van anh
thai cua » than cua, tai cuc, tri cua
hieu ve » hieu va, hieu van
cac vuc » cac nuoc, cac vung, cac cuoc
vuc van » duc van, luc van, thuc van
cua tre » cua te, cuu tre, cua triet
tu sac » tu sach, tu cac, tu bac
tu san » thu san, tu ban, tu can
nang o » nang co, nang ho, nang ro
ve cac » va cac, vien cac
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 ve cac vuc van hanh thai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sac) OR (tu san)) ky nang o lai. hieu ve cac vuc van hanh thai cua tre.
• Adding a wildcard symbol may retrieve word variants: ((tu sac) or (tu san)) ky nang o lai. hieu ve cac vuc van hanh thai cua tre*.