Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
van chat » cao chat
chat duc » chat xuc, chat doc, chet duoc
su sach » so sach
vu sach » vu bach, vu khach
nang xa » nang x, lang xa, nang ma
duc van » duc va, duc tan, duc manh
dinh va » dinh ve, tinh va, sinh va
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, ly nang, v 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) or (vu sach)) y nang xa hoi. hieu van chat duc van ((dinh va) OR (dinh van)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (vu sach)) y nang xa hoi. hieu van chat duc van ((dinh va) OR (dinh van)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su sach) or (vu sach)) y nang xa hoi. hieu van chat duc van ((dinh va) OR (dinh van)) cua tre".
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (vu sach)) y nang xa hoi. hieu van chat duc van ((dinh va) OR (dinh van)) cua tre*.