Perhaps you should try some spelling variations:
ban benh » san benh, ba benh, ban banh
quoc ban » quoc bao, quoc lan, quoc quan
tu sach » thu sach, su sach, tu cach
benh ve » benh va, benh vien, benh viem
van bao » van ban, van dao
van cao » van dao, van hao, van cau
nang ma » tang ma, sang ma, nang cao
te sach » toc sach
cua tre » cua te, cuu tre, cua triet
ma hoi » mai hoi, xa hoi, ma hoa
y nang » ky nang, ly nang, v nang
ve cua » le cua, de cua, te cua

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 (te sach)) y nang ma hoi. hieu ((van cao) OR (van bao)) quoc ban benh ve cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (te sach)) y nang ma hoi. hieu ((van cao) OR (van bao)) quoc ban benh ve cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (te sach)) y nang ma hoi. hieu ((van cao) OR (van bao)) quoc ban benh ve cua tre*".