Perhaps you should try some spelling variations:
van nhanh » van hanh, van khanh, van nhan
van thanh » ban thanh, van tuan
kho tang » cao tang
thai cua » tai cuc, tri cua, dai cua
than cua » nhan cua, ban cua, gian cua
sai kho » dai kho, tai khoa, dai khoa
cao duc » dao duc, cao suc, giao duc
hieu ve » hieu va, hieu van
tang xa » trang xa, tang ma, lang xa
ve cao » va cao, ve bao, ve cac
su sai » su tai, su hai, su dai

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sai kho tang xa hoi. hieu ve cao duc ((van nhanh) OR (van thanh)) ((than cua) or (thai cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sai kho tang xa hoi. hieu ve cao duc ((van nhanh) OR (van thanh)) ((than cua) OR (thai cua)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sai kho tang xa hoi. hieu ve cao duc ((van nhanh) OR (van thanh)) ((than cua) or (thai cua)) tre".
• Adding a wildcard symbol may retrieve word variants: su sai kho tang xa hoi. hieu ve cao duc ((van nhanh) OR (van thanh)) ((than cua) or (thai cua)) tre*.