Perhaps you should try some spelling variations:
tinh khong » tinh khang, tinh huong, benh khong
ngan cong » nganh cong, nganh nong, ngan hang
thuy hanh » thuc hanh, thuy anh, thuy canh
hanh tinh » hanh trinh, nhanh tinh, thanh tinh
khong khi » khong he
hoc sach » hoc sinh, hoc cac
cong khi » cong thai, co khi, cong ha
hoc anh » hoc nganh, hoc nhanh, ngoc anh

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: (( ((hoc sach) OR (hoc anh)) ngan cong khi đong luc ) OR ( thuy hanh tinh khong khi đong luc ))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( ((hoc sach) OR (hoc anh)) ngan cong khi đong luc ) or ( thuy hanh tinh khong khi đong luc ))~".
• Adding a wildcard symbol may retrieve word variants: (( ((hoc sach) OR (hoc anh)) ngan cong khi đong luc ) or ( thuy hanh tinh khong khi đong luc ))*.