Perhaps you should try some spelling variations:
doanh dan » doanh ban, doanh van, doanh dao
va doanh » van doanh, vay doanh, va danh
tu sach » thu sach, su sach, te sach
nang ma » tang ma, sang ma, nang cao
hieu ve » hieu va, hieu van
dan cua » dan ca, ban cua, dai cua
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, ly nang, v nang
ma hoi » mai hoi, xa hoi, ma hoa
soc va » hoc va, loc va, doc va

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 y nang ma hoi. ((hieu ve) or (lieu va)) cham soc va doanh dan cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y nang ma hoi. ((hieu ve) OR (lieu va)) cham soc va doanh dan cua tre*.