Perhaps you should try some spelling variations:
doc sach » hoc sach, toc sach, nuoc sach
dung may » dung va, dung tai, mang may
cam duc » cao duc, pham duc, nam duoc
dat cua » dai cua, day cua, mat cua
anh dat » thanh dat, lanh dao, dinh dat
ban anh » ban hanh, ban banh, ban danh
cua tre » cua te, cuu tre, cua triet
hieu ve » hieu va, hieu van
dan tay » ban tay, dao tay, gian tay

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 y ((dung may) or (dan tay)) hoi. hieu ve ((cam duc) or (cam xuc)) ban anh dat cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc sach y ((dung may) OR (dan tay)) hoi. hieu ve ((cam duc) OR (cam xuc)) ban anh dat cua tre.
• Adding a wildcard symbol may retrieve word variants: doc sach y ((dung may) or (dan tay)) hoi. hieu ve ((cam duc) or (cam xuc)) ban anh dat cua tre*.