Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
xang xa » lang xa, mang xa, ang xa
ve cham » va cham, ve chat, ve chim
vu cham » va cham, vu kham, tu cham
va dinh » van dinh, va kinh, va tinh
van cuu » van cau, van chu, van cu
cuu tre » cua tre, cau tren, cau treo

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((te sach) OR (toc sach)) ty xang xa hoi. hieu ((ve cham) or (vu cham)) hoc va dinh van cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) ty xang xa hoi. hieu ((ve cham) OR (vu cham)) hoc va dinh van cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) OR (toc sach)) ty xang xa hoi. hieu ((ve cham) or (vu cham)) hoc va dinh van cuu tre".
• Adding a wildcard symbol may retrieve word variants: ((te sach) OR (toc sach)) ty xang xa hoi. hieu ((ve cham) or (vu cham)) hoc va dinh van cuu tre*.