Perhaps you should try some spelling variations:
sach thu » sach thue, sach thieu, sach tham
thu nang » thi nang, thu hang, thu bang
tu sach » thu sach, su sach, te sach
hieu va » lieu va, hieu qua
cam cuc » cam xuc, cham cuu, pham cuc
cuc ban » cua ban, cac ban, cuu ban
ban dan » ban hang, ban hanh, ban quan
cua tre » cua te, cuu tre, cua triet
va cam » va cham, va cac, va cao
x hoi » xa hoi, o hoi, 5 hoi

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) OR (x ho)). hieu va cam cuc ban dan _ cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach thu nang ((x hoi) OR (x ho)). hieu va cam cuc ban dan _ cua tre*".