Perhaps you should try some spelling variations:
khau thuong » khac thuong, khai thuong, khanh thuong
truoc cach » cuoc cach, truoc cang
khau thong » khap thong, khau tong, khac thuong
phan thong » phan thuong, phan hong, phan tong
sach tham » sach nha
thuc cach » thuoc sach, thuc hanh, tuc cac
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 tham ((truoc cach) OR (thuc cach)) khoa ((((khau thong) or (khau thuong))) or (phan thong))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach tham ((truoc cach) OR (thuc cach)) khoa ((((khau thong) OR (khau thuong))) OR (phan thong)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach tham ((truoc cach) OR (thuc cach)) khoa ((((khau thong) or (khau thuong))) or (phan thong))".
• Adding a wildcard symbol may retrieve word variants: tu sach tham ((truoc cach) OR (thuc cach)) khoa ((((khau thong) or (khau thuong))) or (phan thong))*.