Perhaps you should try some spelling variations:
vien cac » vien bach, vien dai, vien da
thuc day » thuc dan, thuc vat
day hanh » day nhanh, day thanh, dao hanh
va trien » va truyen, va thiet, va tuyen
so sach » so sanh, bo sach, co sach
sach ky » sac ky, sach y, sach ty
hanh de » hanh ve, hanh kem
ve cam » ve cham, ve cac, va cam
x hoi » xa hoi, o hoi, x ho
de va » de van, te va, ke va

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: so sach ky nang x hoi. hieu ((ve cam) or (vien cac)) thuc day hanh de va trien~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ky nang x hoi. hieu ((ve cam) OR (vien cac)) thuc day hanh de va trien.
• Adding a wildcard symbol may retrieve word variants: so sach ky nang x hoi. hieu ((ve cam) or (vien cac)) thuc day hanh de va trien*.