Perhaps you should try some spelling variations:
thien van » thi van
sach bai » sach dao, sach xa
hat dan » hat van, mat dan, nhat danh
duc hat » duc phat, duc hau, duc ha
cau duc » cao duc, cau luc, chu duc
cua tre » cua te, cuu tre, cua triet
hieu va » lieu va, hieu qua
nang xa » nang x, lang xa, nang ma
dan va » doan va, dan ca, ban va
va cua » va chua, via cua, ca cua

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: tu ((sach bai) OR (cac bai)) nang xa hoi. ((thien van) OR (hieu va)) cau duc hat dan va cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach bai) OR (cac bai)) nang xa hoi. ((thien van) or (hieu va)) cau duc hat dan va cua tre~".
• Adding a wildcard symbol may retrieve word variants: tu ((sach bai) OR (cac bai)) nang xa hoi. ((thien van) or (hieu va)) cau duc hat dan va cua tre*.