Perhaps you should try some spelling variations:
phan thong » phan thuong, phan hong, phan tong
thuc doanh » thuc hanh, thuc dan, chuc danh
doanh khoa » toan khoa
tham thuc » nham thuc, pham thuc, tam thuc
doc sach » hoc sach, toc sach, nuoc sach
sach tri » sach tai, sach tren, sach truc
khoa he » hoa he, khoa hoc, khong he
bao co » bao cao, ban co, bao ho
su sac » su sach, su xac
su cac » tu cac, su cao, su can

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (( doc sach tri du bao co phan thong ) or ( ((su sac) OR (su cac)) tham thuc doanh khoa he thong ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( doc sach tri du bao co phan thong ) OR ( ((su sac) OR (su cac)) tham thuc doanh khoa he thong )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( doc sach tri du bao co phan thong ) or ( ((su sac) OR (su cac)) tham thuc doanh khoa he thong ))".
• Adding a wildcard symbol may retrieve word variants: (( doc sach tri du bao co phan thong ) or ( ((su sac) OR (su cac)) tham thuc doanh khoa he thong ))*.