Perhaps you should try some spelling variations:
thien van » thi van
thanh dat » thanh san, thanh hai, thanh van
su sach » so sach, vu sach
van cam » van nam, van lam, van cau
dat cua » dai cua, day cua, mat cua
cua tre » cua te, cuu tre, cua triet
y lang » o lang, tay lang, yen lang
_ lang » o lang, _ land
xuc va » duc va, luc va, xac va
tuc va » thuc va, truc va, tuc xa

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 ((y lang) OR (_ lang)) xa hoi. thien van cam ((xuc va) or (tuc va)) thanh dat cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ((y lang) OR (_ lang)) xa hoi. thien van cam ((xuc va) OR (tuc va)) thanh dat cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ((y lang) OR (_ lang)) xa hoi. thien van cam ((xuc va) or (tuc va)) thanh dat cua tre".
• Adding a wildcard symbol may retrieve word variants: su sach ((y lang) OR (_ lang)) xa hoi. thien van cam ((xuc va) or (tuc va)) thanh dat cua tre*.