Perhaps you should try some spelling variations:
thanh thai » thanh hai, thanh tai, nhanh thai
thai cua » than cua, tai cuc, tri cua
cua tre » cua te, cuu tre, cua triet
ve cham » va cham, ve chat, vu cham
hieu ve » hieu va, hieu van
mai hoi » mai khoi, lai hoi, mai doi
dai hoi » dai hoc, dai hai, dai moi
ky dang » ky nang, ky danh
san ky » sang ky, van ky, dan ky
luc va » tuc va, loc va
tu san » thu san, tu ban, tu can

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: tu san ky dang ((mai hoi) OR (dai hoi)). hieu ve cham ((luc va) or (duc va)) thanh thai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu san ky dang ((mai hoi) OR (dai hoi)). hieu ve cham ((luc va) OR (duc va)) thanh thai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu san ky dang ((mai hoi) OR (dai hoi)). hieu ve cham ((luc va) or (duc va)) thanh thai cua tre".
• Adding a wildcard symbol may retrieve word variants: tu san ky dang ((mai hoi) OR (dai hoi)). hieu ve cham ((luc va) or (duc va)) thanh thai cua tre*.