Perhaps you should try some spelling variations:
dang dinh » dang sinh, dang dieu, dang hanh
doc sach » hoc sach, toc sach, nuoc sach
dan dinh » doan dinh, van dinh, dao dinh
hoc cac » hoc cao
cam luc » cam xuc, cau luc
hieu va » lieu va, hieu qua
cuu tre » cua tre, cau tren, cau treo
nang o » nang co, nang ho, nang ro
luc va » duc va, tuc va, loc va
v nang » va nang, vu nang, van nang
va cam » va cham, va cac, va cao
o hoc » co hoc, mo hoc, so hoc

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((hoc cac) or (doc sach)) v nang o hoc. hieu va cam luc va ((dan dinh) OR (dang dinh)) cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((hoc cac) OR (doc sach)) v nang o hoc. hieu va cam luc va ((dan dinh) OR (dang dinh)) cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((hoc cac) or (doc sach)) v nang o hoc. hieu va cam luc va ((dan dinh) OR (dang dinh)) cuu tre".
• Adding a wildcard symbol may retrieve word variants: ((hoc cac) or (doc sach)) v nang o hoc. hieu va cam luc va ((dan dinh) OR (dang dinh)) cuu tre*.