Perhaps you should try some spelling variations:
sach thu » sach thue, sach thieu, sach tham
thu nang » thi nang, thu hang, thu bang
ban hanh » ban hang
tu sach » thu sach, su sach, te sach
hanh da » hanh dao, hanh dua, hanh va
cuc ban » cua ban, cac ban, cuu ban
cua tre » cua te, cuu tre, cua triet
va cham » va chat, va tham
va cam » va cao, va cai, va cau
da cua » dai cua, day cua, dan cua
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach thu nang x hoi. hieu ((((va cam) OR (va cham))) or (va cac)) cuc ban hanh da cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach thu nang x hoi. hieu ((((va cam) OR (va cham))) OR (va cac)) cuc ban hanh da cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach thu nang x hoi. hieu ((((va cam) OR (va cham))) or (va cac)) cuc ban hanh da cua tre*".