Perhaps you should try some spelling variations:
thu sach » thuat sach, thuoc sach, thu hoach
tinh vai » tinh va, tinh hai, tinh bai
ban tinh » ban thanh, quan tinh, ban hanh
tu sach » su sach, te sach, tu cach
cac cuc » cac cuoc, cac nuoc, cac cach
vai cua » dai cua, hai cua, lai cua
cac cua » cach cua, cac qua, ca cua
cua tre » cua te, cuu tre, cua triet
hieu ve » hieu va, hieu van
dang xa » dang xay, lang xa, dang ha
ky dang » ky nang, ky danh

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) OR (thu sach)) ky dang xa hoi. hieu ve ((cac cuc) or (cac cua)) ban tinh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu sach)) ky dang xa hoi. hieu ve ((cac cuc) OR (cac cua)) ban tinh vai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) OR (thu sach)) ky dang xa hoi. hieu ve ((cac cuc) or (cac cua)) ban tinh vai cua tre".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) OR (thu sach)) ky dang xa hoi. hieu ve ((cac cuc) or (cac cua)) ban tinh vai cua tre*.