Perhaps you should try some spelling variations:
van thanh » ban thanh, van tuan
thanh vi » hanh vi, thanh va, thanh ve
thu sach » thuat sach, thuoc sach, thu hoach
tu sach » su sach, te sach, tu cach
duc van » duc va, duc tan, duc manh
cac duc » cac du, cao duc, cac dac
hieu ve » hieu va, hieu van
dai hoi » dai hoc, dai hai, dai moi
nha hoc » nha thuoc, khoa hoc, nha nuoc
mai hoi » mai khoi, lai hoi, mai doi
ve cac » va cac, vien cac
y nang » ky nang, ly nang, v nang
vi nha » ve nha, va nha, li nha

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu sach) or (thu sach)) y nang ((mai hoi) or (dai hoi)). hieu ve cac duc van thanh vi nha hoc~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu sach)) y nang ((mai hoi) OR (dai hoi)). hieu ve cac duc van thanh vi nha hoc*.