Perhaps you should try some spelling variations:
toan thai » toan tai, toan phai, hoang thai
thai cua » than cua, tai cuc, tri cua
tu sach » thu sach, su sach, te sach
nang xa » nang x, lang xa, nang ma
va cham » va chat
va tham » van tham, va thanh, va thuat
va toan » van toan, bai toan, tap toan
cua tre » cua te, cuu tre, cua triet

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 (hoc sinh)) ky nang xa hoi. lieu ((va cham) or (va tham)) duc va toan thai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (hoc sinh)) ky nang xa hoi. lieu ((va cham) OR (va tham)) duc va toan thai cua tre.
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (hoc sinh)) ky nang xa hoi. lieu ((va cham) or (va tham)) duc va toan thai cua tre*.