Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
lang van » tang van, hoang van, giang van
dang van » hoang van, hang va
cua tre » cua te, cuu tre, cua triet
cua van » cua ban, cua vat, cua dan
sac ky » cac ky, sai ky
va nam » van nam, ha nam
va nay » va ngay, va cay
vi cua » vai cua, di cua
tu sac » tu sach, tu cac, tu san

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