Perhaps you should try some spelling variations:
phan thuong » hang thuong, phan xuong
khau thong » khau thuong, khau tong, khac thuong
nguoi sach » nguoi san, nuoc sach
khap thong » phap thong, khac thuong, chap thuong
thuc cach » thuoc sach, truoc cach, thuc hanh
sach dao » lanh dao
tu sach » thu sach, su sach, te sach

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 dao ((thuc cach) or (nguoi sach)) khoa ((((khau thong) OR (khap thong))) or (phan thuong))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach dao ((thuc cach) OR (nguoi sach)) khoa ((((khau thong) OR (khap thong))) OR (phan thuong)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach dao ((thuc cach) or (nguoi sach)) khoa ((((khau thong) OR (khap thong))) or (phan thuong))".
• Adding a wildcard symbol may retrieve word variants: tu sach dao ((thuc cach) or (nguoi sach)) khoa ((((khau thong) OR (khap thong))) or (phan thuong))*.