Perhaps you should try some spelling variations:
ban hanh » ban hang
va thanh » gia thanh, ban thanh, le thanh
va tinh » may tinh
tu sach » thu sach, su sach, te sach
cac duc » cac du, cao duc, cac dac
hieu ve » hieu va, hieu van
nang xa » nang x, lang xa, nang ma
cuu tre » cua tre, cau tren, cau treo
y nang » ky nang, ly nang, v nang
ve cac » va cac, vien cac
di cuu » di cau, di cua, dinh cuu

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 y nang xa hoi. hieu ve cac duc ((ban hanh) or (((va thanh) OR (va tinh)))) di cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y nang xa hoi. hieu ve cac duc ((ban hanh) OR (((va thanh) OR (va tinh)))) di cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach y nang xa hoi. hieu ve cac duc ((ban hanh) or (((va thanh) OR (va tinh)))) di cuu tre".
• Adding a wildcard symbol may retrieve word variants: tu sach y nang xa hoi. hieu ve cac duc ((ban hanh) or (((va thanh) OR (va tinh)))) di cuu tre*.