Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
sach tra » sach tranh, sach tham, sach tren
cham duc » pham duc, cham soc, pham duy
tra nang » thi nang, kha nang, da nang
hieu tu » chieu tu, hieu tuc, lieu tu
hien tu » khien tu, dien tu
va danh » va dinh, va dan, va hanh
x hoi » xa hoi, o hoi, x ho
de su » den su, de tu, da su
ve su » va su

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

• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach tra nang x hoi. ((hieu tu) OR (hien tu)) cham duc va danh ((de su) OR (ve su)) triet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach tra nang x hoi. ((hieu tu) or (hien tu)) cham duc va danh ((de su) OR (ve su)) triet~".
• Adding a wildcard symbol may retrieve word variants: thu sach tra nang x hoi. ((hieu tu) or (hien tu)) cham duc va danh ((de su) OR (ve su)) triet*.