Perhaps you should try some spelling variations:
van tuan » van quan, van ban, anh tuan
tu sach » thu sach, su sach, te sach
hieu va » lieu va, hieu qua
tuan va » toan va, luan va, quan va
duc van » duc va, duc tan, duc manh
cua tre » cua te, cuu tre, cua triet
hieu ve » hieu van
lang xa » lang ha, dang xay, lang van
ky lang » ky nang, ky dang, ky tang
va cua » va chua, via cua, ca cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu sach) or (thu hoach)) ky lang xa hoi. ((hieu ve) or (hieu va)) pham duc van tuan va cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu hoach)) ky lang xa hoi. ((hieu ve) OR (hieu va)) pham duc van tuan va cua tre.
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (thu hoach)) ky lang xa hoi. ((hieu ve) or (hieu va)) pham duc van tuan va cua tre*.