Perhaps you should try some spelling variations:
tinh vai » tinh va, tinh hai, tinh bai
hieu van » hieu va, thien van, lieu va
vai cua » dai cua, hai cua, lai cua
sach ty » sach y, sach tu, sach thu
khu may » chu may, chua may, phuc may
xay hoi » xa hoi, tay hoi, cay phoi
hieu ve » hieu va
sach ly » sach y, sach lo, sach hay
cac khu » cac thu, cac khoi, cac kieu
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) or (sach ty)) van xay hoi. ((hieu ve) OR (hieu van)) cac khu may tinh vai cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach ly) OR (sach ty)) van xay hoi. ((hieu ve) OR (hieu van)) cac khu may tinh vai cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach ly) or (sach ty)) van xay hoi. ((hieu ve) OR (hieu van)) cac khu may tinh vai cua te".
• Adding a wildcard symbol may retrieve word variants: su ((sach ly) or (sach ty)) van xay hoi. ((hieu ve) OR (hieu van)) cac khu may tinh vai cua te*.