Perhaps you should try some spelling variations:
thieu khang » chieu khong, thieu quang
nham thuc » nhan thuc, nam thuc, nham thu
toc sach » hoc sach, doc sach, thuoc sach
dieu cua » dieu tra
va danh » va dinh, va hanh, dia danh
va nham » va cham, va tham, va nha
hieu va » lieu va, hieu qua
khang o » khang a, thang o, khang voi
va dan » ca dan, va dao, va dau
de cua » le cua, te cua
o hoi » co hoi, o hoc, o hai

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 thieu khang o hoi. hieu va nham thuc ((va danh) or (va dan)) ((de cua) or (dieu cua)) tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach thieu khang o hoi. hieu va nham thuc ((va danh) OR (va dan)) ((de cua) OR (dieu cua)) tu.
• Adding a wildcard symbol may retrieve word variants: toc sach thieu khang o hoi. hieu va nham thuc ((va danh) or (va dan)) ((de cua) or (dieu cua)) tu*.