Perhaps you should try some spelling variations:
ban hanh » ban hang
vien cac » vien bach, vien dai, gian cac
xuc ban » duc ban, cuc ban, quoc ban
vien da » vien dai, hien dai
sach ky » sach y, sach ty, sach kem
ca viet » va viet, co viet, hoa viet
nang ma » tang ma, sang ma, nang cao
ma hoi » mai hoi, xa hoi, ma hoa
sac ky » cac ky, sai ky
vi ca » vit ca, li ca, va ca

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 ma hoi. hieu ((vien cac) or (vien da)) xuc ban hanh vi ca viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (sac ky)) nang ma hoi. hieu ((vien cac) OR (vien da)) xuc ban hanh vi ca viet.
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) or (sac ky)) nang ma hoi. hieu ((vien cac) or (vien da)) xuc ban hanh vi ca viet*.