Perhaps you should try some spelling variations:
thuong tinh » khuong tinh, thuong binh, truong tinh
nguoi cong » nguoi muong, nguoi thong, nguoi nung
thong tinh » thong tin, thong minh, trong tinh
sach cha » sach nha, sach ha, sach cua
sach che » sach thue, sach nha, sach cap
nguoi co » nguoi do, nguoi dao, nguoi moi

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 cha) or (sach che)) me ((nguoi cong) or (nguoi co)) ((thong tinh) OR (thuong tinh))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach cha) OR (sach che)) me ((nguoi cong) OR (nguoi co)) ((thong tinh) OR (thuong tinh)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach cha) or (sach che)) me ((nguoi cong) or (nguoi co)) ((thong tinh) OR (thuong tinh))".
• Adding a wildcard symbol may retrieve word variants: tu ((sach cha) or (sach che)) me ((nguoi cong) or (nguoi co)) ((thong tinh) OR (thuong tinh))*.