Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
cuc ban » cua ban, cuu ban, duc ban
cac ban » cac dan, cac van, can ban
hieu va » lieu va, hieu qua
y nang » ky nang, ly nang, v nang
va cam » va cham, va cac, va cao
di cua » dai cua, doi cua, do cua
de cua » le cua, te cua, dieu 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: thu sach y nang x hoi. hieu va cam ((cuc ban) OR (cac ban)) benh ((di cua) or (de cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach y nang x hoi. hieu va cam ((cuc ban) OR (cac ban)) benh ((di cua) OR (de cua)) tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach y nang x hoi. hieu va cam ((cuc ban) OR (cac ban)) benh ((di cua) or (de cua)) tre*".