Perhaps you should try some spelling variations:
tham thuc » nham thuc, pham thuc, tam thuc
thien van » thi van
van tham » van thanh, van tuan, van chat
toc sach » doc sach, thuoc sach, nuoc sach
hoc sach » hoc sinh, hoc cac, hoc anh
va dinh » van dinh, va tinh, vu dinh
va kinh » va tinh, qua kinh
dau cua » dai cua, day cua, cau cua
cua tre » cua te, cuu tre, cua triet
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((toc sach) or (hoc sach)) ky nang x hoi. thien van tham thuc ((va dinh) or (va kinh)) dau cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((toc sach) OR (hoc sach)) ky nang x hoi. thien van tham thuc ((va dinh) OR (va kinh)) dau cua tre.
• Adding a wildcard symbol may retrieve word variants: ((toc sach) or (hoc sach)) ky nang x hoi. thien van tham thuc ((va dinh) or (va kinh)) dau cua tre*.