Perhaps you should try some spelling variations:
hanh via » hanh va, anh va, hanh ve
su sach » so sach, vu sach
cua tre » cua te, cuu tre, cua triet
hieu va » lieu va, hieu qua
nang ma » tang ma, sang ma, nang cao
bao bo » bac bo, ban bo, nao bo
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.

• Performing a fuzzy search may retrieve terms with similar spellings: su sach y nang ma hoi. hieu va ((bao bo) or (nam bo)) va ((hanh via) OR (hanh vi)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach y nang ma hoi. hieu va ((bao bo) OR (nam bo)) va ((hanh via) OR (hanh vi)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach y nang ma hoi. hieu va ((bao bo) or (nam bo)) va ((hanh via) OR (hanh vi)) cua tre".
• Adding a wildcard symbol may retrieve word variants: su sach y nang ma hoi. hieu va ((bao bo) or (nam bo)) va ((hanh via) OR (hanh vi)) cua tre*.