Perhaps you should try some spelling variations:
hieu van » thien van, lieu va, hieu ve
va thanh » gia thanh, ban thanh, va tinh
thanh va » thanh van, hanh va, thanh ha
chua tre » chua tri, cua tre, chua trieu
su sach » so sach, vu sach
ky dang » ky danh
hieu va » lieu va, hieu qua
cau luc » cau truc, cau phuc
va chua » vua chua, ca chua, va chu
luc va » duc va, tuc va, loc va

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