Perhaps you should try some spelling variations:
thanh dat » thanh hai, thanh van, thanh ha
te sach » toc sach
cac dac » cac dan, cac dai, cac bac
cua tre » cua te, cuu tre, cua triet
cac duc » cac du, cao duc, cac nuoc
hieu ve » hieu va, hieu van
nang ma » tang ma, sang ma, nang cao
y nang » ky nang, ly nang, v nang
ma hoi » mai hoi, xa hoi, ma hoa

You may be able to get more results by adjusting your search query.

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