Perhaps you should try some spelling variations:
vien cac » vien bach, vien dai, gian cac
su sach » so sach, vu sach
vien da » vien dai, hien dai
va hanh » van hanh, va thanh, va danh
cua tre » cua te, cuu tre, cua triet
ly nang » ky nang, ly hang, ly vang
sach ly » sach y, sach lo, sach ty
thu va » thuc va, thue va, tu va
vi cua » vai cua, di cua
x hoi » xa hoi, o hoi, x ho

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 x hoi. hieu ((((vien cac) OR (vien da))) or (va cac)) thu va hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ly nang x hoi. hieu ((((vien cac) OR (vien da))) OR (va cac)) thu va hanh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ly nang x hoi. hieu ((((vien cac) OR (vien da))) or (va cac)) thu va hanh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: su sach ly nang x hoi. hieu ((((vien cac) OR (vien da))) or (va cac)) thu va hanh vi cua tre*.