Perhaps you should try some spelling variations:
thanh nhat » thanh nhan, thanh nha, thanh hai
van thanh » ban thanh, van tuan
sach dao » lanh dao
vu sach » vu bach, su sach, vu khach
ky khi » ky thi
ly khi » ly chi
dao y » dao ly, dao _, dao o
y khi » my khi, y chi, y nhi

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

• If you are trying to use Boolean operators, they must be ALL CAPS: (( vu sach dao y khi đong luc ) OR ( van thanh nhat ((ky khi) OR (ly khi)) đong luc ))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( vu sach dao y khi đong luc ) or ( van thanh nhat ((ky khi) OR (ly khi)) đong luc ))~".
• Adding a wildcard symbol may retrieve word variants: (( vu sach dao y khi đong luc ) or ( van thanh nhat ((ky khi) OR (ly khi)) đong luc ))*.