Perhaps you should try some spelling variations:
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va, hieu van
duc ban » duc tan, duc van, dua ban
qua ban » cua ban, qua quan
hanh ve » hanh vi, hanh va, hanh kem
su viet » so viet
ve cac » va cac, vien cac
x hoi » xa hoi, o hoi, x ho
ve su » va su

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 ky nang x hoi. hieu ve cac ((duc ban) or (qua ban)) hanh ve su viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang x hoi. hieu ve cac ((duc ban) OR (qua ban)) hanh ve su viet*.