Perhaps you should try some spelling variations:
tang mai » tang ma, tang tai, lang mai
hanh van » thanh van, khanh van, hanh va
ky tang » ky nang, ky dang, kho tang
mai hoi » mai khoi, dai hoi, lai hoi
cuu tre » cua tre, cau tren, cau treo
ve cao » va cao, ve bao, ve co
ve cac » va cac, vien cac

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu cac ky tang mai hoi. hieu ((ve cao) OR (ve cac)) duc va ((hanh van) or (hanh vi)) cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu cac ky tang mai hoi. hieu ((ve cao) OR (ve cac)) duc va ((hanh van) OR (hanh vi)) cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu cac ky tang mai hoi. hieu ((ve cao) OR (ve cac)) duc va ((hanh van) or (hanh vi)) cuu tre".
• Adding a wildcard symbol may retrieve word variants: tu cac ky tang mai hoi. hieu ((ve cao) OR (ve cac)) duc va ((hanh van) or (hanh vi)) cuu tre*.