Perhaps you should try some spelling variations:
doc sach » hoc sach, toc sach, nuoc sach
sach thu » sach thue, sach thieu, sach tham
thu nang » thi nang, thu hang, thu bang
thai cua » than cua, tai cuc, tri cua
nang xa » nang x, lang xa, nang ma
hieu va » lieu va, hieu qua
cac luc » cau luc, coc luc, cac nuoc
va hanh » van hanh, va thanh, va danh
lai cua » dai cua, hai cua, lai chau
luc va » duc va, tuc va, loc va

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

• Performing a fuzzy search may retrieve terms with similar spellings: doc sach thu nang xa hoi. hieu va cac luc va hanh ((lai cua) or (thai cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc sach thu nang xa hoi. hieu va cac luc va hanh ((lai cua) OR (thai cua)) tre.
• Adding a wildcard symbol may retrieve word variants: doc sach thu nang xa hoi. hieu va cac luc va hanh ((lai cua) or (thai cua)) tre*.