Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
dua tren » dung tren
su sach » so sach, vu sach
sach ly » sach y, sach lo, sach ty
ly nang » ky nang, ly hang, ly vang
nang xa » nang x, lang xa, nang ma
thu van » thuc van, thuy van, tu van
cua tre » cua te, cuu tre, cua triet
ve cac » vien cac

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ly nang xa hoi. hieu ((ve cac) or (va cac)) thu van hanh vi ((dua tren) or (cua tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ly nang xa hoi. hieu ((ve cac) OR (va cac)) thu van hanh vi ((dua tren) OR (cua tre)).
• Adding a wildcard symbol may retrieve word variants: su sach ly nang xa hoi. hieu ((ve cac) or (va cac)) thu van hanh vi ((dua tren) or (cua tre))*.