Perhaps you should try some spelling variations:
vien cac » vien bach, vien dai, vien da
thanh ve » hanh ve, thanh va, thanh vien
thanh vi » hanh vi, thanh va, nhanh vi
duc ban » duc tan, duc van, dua ban
so sach » so sanh, bo sach, co sach
sach ty » sach y, sach tu, sach thu
nang xa » nang x, lang xa, nang ma
ty nang » ky nang, ty xang, ty hang
cua tre » cua te, cuu tre, cua triet
ve cam » ve cham, ve cac, va cam

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 ty nang xa hoi. hieu ((ve cam) or (vien cac)) duc ban ((thanh vi) or (thanh ve)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ty nang xa hoi. hieu ((ve cam) OR (vien cac)) duc ban ((thanh vi) OR (thanh ve)) cua tre.
• Adding a wildcard symbol may retrieve word variants: so sach ty nang xa hoi. hieu ((ve cam) or (vien cac)) duc ban ((thanh vi) or (thanh ve)) cua tre*.