Perhaps you should try some spelling variations:
van thanh » ban thanh, van tuan
van hanh » ban hanh, van anh, van ban
thai cuu » thai cua, tai cuc, thi cuc
thu canh » thuc hanh, thu cong, thu ban
cuu tre » cua tre, cau tren, cau treo
hieu ve » hieu va, hieu van
cac duc » cac du, cao duc, cac dac
tu bac » tu ban, tu cac, tu bat
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 bac) or (thu canh)) ky nang o lai. hieu ve cac duc ((van hanh) or (van thanh)) thai cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu bac) OR (thu canh)) ky nang o lai. hieu ve cac duc ((van hanh) OR (van thanh)) thai cuu tre.
• Adding a wildcard symbol may retrieve word variants: ((tu bac) or (thu canh)) ky nang o lai. hieu ve cac duc ((van hanh) or (van thanh)) thai cuu tre*.