Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
thien van » thi van
thanh vi » hanh vi, thanh va, thanh ve
quoc ban » quoc bao, quoc lan, quoc quan
nam quoc » nam duoc, nam buoc, nam thuoc
tu sach » thu sach, su sach, tu cach
te sach » toc sach
cuu tre » cua tre, cau tren, cau treo
vi cuu » vi luu, vinh cuu

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)) ky ((mang may) or (nang cao)) hoi. thien van nam quoc ban thanh vi cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (te sach)) ky ((mang may) OR (nang cao)) hoi. thien van nam quoc ban thanh vi cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) OR (te sach)) ky ((mang may) or (nang cao)) hoi. thien van nam quoc ban thanh vi cuu tre".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) OR (te sach)) ky ((mang may) or (nang cao)) hoi. thien van nam quoc ban thanh vi cuu tre*.