Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
thu nang » thi nang, thu hang, thu bang
hang doi » hang di, hang loi, huong doi
doi cua » dai cua, hoi cua
nang xa » nang x, lang xa, nang ma
qua cam » qua cham, qua ca, qua cai
va hang » van hang, va nang, va lang
qua cac » cua cac
cua te » cua tu
xuc va » duc va, tuc va, luc va

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)) thu nang xa hoi. hieu ((qua cam) OR (qua cac)) xuc va hang doi cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) thu nang xa hoi. hieu ((qua cam) OR (qua cac)) xuc va hang doi cua te*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) or (toc sach)) thu nang xa hoi. hieu ((qua cam) OR (qua cac)) xuc va hang doi cua te*".