Perhaps you should try some spelling variations:
va thanh » gia thanh, ban thanh, le thanh
tu sach » thu sach, su sach, te sach
cam luc » cam xuc, cau luc
va tinh » may tinh
cua tre » cua te, cuu tre, cua triet
hieu ve » hieu va, hieu van
mai hoi » mai khoi, dai hoi, lai hoi
ty nang » ty xang, ty hang, ly nang
ve cam » ve cham, ve cac, va cam

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 ((ty nang) or (ky nang)) mai hoi. hieu ve cam luc ((va thanh) OR (va tinh)) dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((ty nang) OR (ky nang)) mai hoi. hieu ve cam luc ((va thanh) OR (va tinh)) dai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((ty nang) or (ky nang)) mai hoi. hieu ve cam luc ((va thanh) OR (va tinh)) dai cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ((ty nang) or (ky nang)) mai hoi. hieu ve cam luc ((va thanh) OR (va tinh)) dai cua tre*.