Perhaps you should try some spelling variations:
sach thien » sach thieu, sach tien, cach thien
thien nang » thien bang, thien dang, trien nang
toc sach » hoc sach, doc sach, thuoc sach
van hanh » van thanh, ban hanh, van anh
nang xa » nang x, lang xa, nang ma
duc van » duc va, duc tan, duc manh
ve cac » vien cac
vi cua » vai cua, di cua
cua cu » cua chu, cua cau, cua 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: toc sach thien nang xa hoi. hieu ((ve cac) OR (va cac)) duc van hanh vi cua cu~.
• Adding a wildcard symbol may retrieve word variants: toc sach thien nang xa hoi. hieu ((ve cac) or (va cac)) duc van hanh vi cua cu*.