Perhaps you should try some spelling variations:
ban hanh » ban hang
van hanh » van thanh, van anh, van ban
nang ma » tang ma, sang ma, nang cao
cua tre » cua te, cuu tre, cua triet
tu sac » tu sach, tu cac, tu san
sac ky » cac ky, sai ky
ma hoi » mai hoi, xa hoi, ma hoa
vi cua » vai cua, di cua

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 ky nang ma hoi. hieu ((van lam) OR (van nam)) xuc ((ban hanh) or (van hanh)) vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sac ky nang ma hoi. hieu ((van lam) OR (van nam)) xuc ((ban hanh) OR (van hanh)) vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sac ky nang ma hoi. hieu ((van lam) OR (van nam)) xuc ((ban hanh) or (van hanh)) vi cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sac ky nang ma hoi. hieu ((van lam) OR (van nam)) xuc ((ban hanh) or (van hanh)) vi cua tre*.