Perhaps you should try some spelling variations:
sach trien » sach tien, sach tren, sach thieu
trien thuc » trien thuoc, tren thuc, trien thuat
thuc doanh » thuc hanh, thuc dan, chuc danh
khoa thong » hoa thong, thoai thong, pho thong
cach khuan » cac khoan, cach hoan
doanh hoc » danh hoc, doanh khoa, doanh hoan
sach truc » cach thuc, sach tren, sach thu
truc thuc » truc thuoc, thuc thuc, truc thuy
thuc cach » thuoc sach, truoc cach, thuc hanh
hoc khoa » hoc pho
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 trien thuc doanh hoc khoa thong ) or ( tu sach truc thuc cach khuan khoa thong ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tu sach trien thuc doanh hoc khoa thong ) OR ( tu sach truc thuc cach khuan khoa thong )).
• Adding a wildcard symbol may retrieve word variants: (( tu sach trien thuc doanh hoc khoa thong ) or ( tu sach truc thuc cach khuan khoa thong ))*.