Perhaps you should try some spelling variations:
thanh hai » thanh phan, thanh hoa, thanh san
su sach » so sach, vu sach
nang xa » nang x, lang xa, nang ma
duc van » duc tan, duc manh, duc phan
hai cua » thai cua, dai cua, hoi cua
cua tre » cua te, cuu tre, cua triet
sach v » sach va, sach y, sach 2
v nang » va nang, vu nang, van nang

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 v nang xa hoi. ((hieu qua) or (lieu va)) cao ((duc van) OR (duc va)) thanh hai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach v nang xa hoi. ((hieu qua) OR (lieu va)) cao ((duc van) OR (duc va)) thanh hai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach v nang xa hoi. ((hieu qua) or (lieu va)) cao ((duc van) OR (duc va)) thanh hai cua tre".
• Adding a wildcard symbol may retrieve word variants: su sach v nang xa hoi. ((hieu qua) or (lieu va)) cao ((duc van) OR (duc va)) thanh hai cua tre*.