Perhaps you should try some spelling variations:
cau tren » cu tren, dau tren, ca tren
thanh vi » thanh va, thanh ve, nhanh vi
duc ban » duc tan, duc van, dua ban
tre dan » tre dang, te dan, tre can
tang xa » trang xa, tang ma, lang xa
ky tang » ky nang, ky dang, kho tang
dan ky » van ky
ve cau » va cau, ve cac, le cau
ke cau » ket cau

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

• Performing a fuzzy search may retrieve terms with similar spellings: tre dan ky tang xa hoi. hieu ((ve cau) or (ke cau)) duc ban ((thanh vi) or (hanh vi)) cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tre dan ky tang xa hoi. hieu ((ve cau) OR (ke cau)) duc ban ((thanh vi) OR (hanh vi)) cau tren.
• Adding a wildcard symbol may retrieve word variants: tre dan ky tang xa hoi. hieu ((ve cau) or (ke cau)) duc ban ((thanh vi) or (hanh vi)) cau tren*.