Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
sach thu » sach thue, sach thieu, sach tham
thu nang » thi nang, thu hang, thu bang
danh vai » danh sai, danh va, doanh van
nang xa » nang x, lang xa, nang ma
qua cao » qua cac, qua ca, qua cai
vai cua » dai cua, hai cua, lai cua
su van » tu van, vu van
cua te » cua tu
su va » tu va

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 thu nang xa hoi. hieu qua cao ((su va) OR (su van)) danh vai cua te~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach thu nang xa hoi. hieu qua cao ((su va) OR (su van)) danh vai cua te".
• Adding a wildcard symbol may retrieve word variants: toc sach thu nang xa hoi. hieu qua cao ((su va) OR (su van)) danh vai cua te*.