Perhaps you should try some spelling variations:
su sach » so sach, vu sach
cac thu » cach thuc, cac thoi
tinh vi » trinh vi, tinh voi, tinh va
xay hoi » xa hoi, tay hoi, cay phoi
hieu ve » hieu va, hieu van
cac khu » cac khoi, cac kieu
vi cua » vai cua, di cua
ly van » le van, ly von, lo van
cua te » cua tu

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 ((ly van) OR (ly va)) xay hoi. hieu ve ((cac khu) or (cac thu)) may tinh vi cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ((ly van) OR (ly va)) xay hoi. hieu ve ((cac khu) OR (cac thu)) may tinh vi cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ((ly van) OR (ly va)) xay hoi. hieu ve ((cac khu) or (cac thu)) may tinh vi cua te".
• Adding a wildcard symbol may retrieve word variants: su sach ((ly van) OR (ly va)) xay hoi. hieu ve ((cac khu) or (cac thu)) may tinh vi cua te*.