Perhaps you should try some spelling variations:
cua triet » su triet, va triet
toc sach » hoc sach, doc sach, thuoc sach
cua viet » ca viet, hoa viet, cua vat
quang xa » quan xa, quang ma, quang va
hieu va » lieu va, hieu qua
thuc va » thuc vat, thuc dan, thuc day
danh vi » hanh vi, dinh vi, danh di
x quang » xa quang, _ quang, vu quang
loc va » hoc va, luc va
sach x » sach xa, sach xu, sach y

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

• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach x quang xa hoi. hieu va cac ((loc va) OR (thuc va)) danh vi ((cua triet) OR (cua viet))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach x quang xa hoi. hieu va cac ((loc va) or (thuc va)) danh vi ((cua triet) OR (cua viet))~".
• Adding a wildcard symbol may retrieve word variants: toc sach x quang xa hoi. hieu va cac ((loc va) or (thuc va)) danh vi ((cua triet) OR (cua viet))*.