Perhaps you should try some spelling variations:
thanh dong » thanh duong, thanh cong, hanh dong
day thanh » dao thanh, dat thanh, da thanh
toc sach » hoc sach, doc sach, thuoc sach
hieu van » hieu va, thien van, lieu va
nam thuc » nam thuoc, am thuc, nam thu
thuc day » thuc dan, thuc vat
dong cua » dung cua, cong cua, huong cua
cua viet » ca viet, hoa viet, cua vat
sach ky » sac ky, sach y, sach ty
lang xa » dang xay, lang van
lang ha » long ha

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 ky ((lang xa) or (lang ha)) hoi. hieu van nam thuc day thanh dong cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ky ((lang xa) OR (lang ha)) hoi. hieu van nam thuc day thanh dong cua viet.
• Adding a wildcard symbol may retrieve word variants: toc sach ky ((lang xa) or (lang ha)) hoi. hieu van nam thuc day thanh dong cua viet*.