Perhaps you should try some spelling variations:
thanh hai » thanh phan, thanh hoa
hieu van » hieu va, thien van, lieu va
ky tang » ky dang, kho tang, ky trong
van lam » van nam
lam duc » lam duoc, pham duc, nam duoc
duc van » duc va, duc tan, duc manh
cua tre » cua te, cuu tre, cua triet
su xac » pu xac, su cac

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

• Performing a fuzzy search may retrieve terms with similar spellings: su xac ((ky tang) or (ky nang)) xa hoi. hieu van lam duc van ((thanh hai) OR (thanh san)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su xac ((ky tang) OR (ky nang)) xa hoi. hieu van lam duc van ((thanh hai) OR (thanh san)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su xac ((ky tang) or (ky nang)) xa hoi. hieu van lam duc van ((thanh hai) OR (thanh san)) cua tre".
• Adding a wildcard symbol may retrieve word variants: su xac ((ky tang) or (ky nang)) xa hoi. hieu van lam duc van ((thanh hai) OR (thanh san)) cua tre*.