Perhaps you should try some spelling variations:
sach ky » sach y, sach ty, sach kem
hanh ve » hanh vi, hanh va, hanh kem
qua ban » cua ban, qua quan
duc ban » duc tan, duc van, dua ban
hieu ve » hieu va, hieu van
su viet » so viet
ve cac » va cac, vien cac
sac ky » cac ky, sai ky
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) OR (sac 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) OR (sac ky)) nang x hoi. hieu ve cac ((duc ban) OR (qua ban)) hanh ve su viet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ky) OR (sac ky)) nang x hoi. hieu ve cac ((duc ban) or (qua ban)) hanh ve su viet*".