Perhaps you should try some spelling variations:
dung doi » huong doi, dung co, dung mo
vu sach » vu bach, su sach, vu khach
nang ma » tang ma, sang ma, nang cao
hieu ve » hieu va, hieu van
cam tuc » cam xuc, cam tu, nam thuc
cua tre » cua te, cuu tre, cua triet
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: vu sach y nang ma hoi. ((hieu ve) or (lieu va)) cam tuc xa ((dung doi) OR (dung tai)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach y nang ma hoi. ((hieu ve) OR (lieu va)) cam tuc xa ((dung doi) OR (dung tai)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu sach y nang ma hoi. ((hieu ve) or (lieu va)) cam tuc xa ((dung doi) OR (dung tai)) cua tre".
• Adding a wildcard symbol may retrieve word variants: vu sach y nang ma hoi. ((hieu ve) or (lieu va)) cam tuc xa ((dung doi) OR (dung tai)) cua tre*.