Perhaps you should try some spelling variations:
cach khoan » cac khoan, cach hoan, bach khoa
khau thong » khau thuong, khap thong, khau tong
khoan phai » khong phai, khoa phau, khoan hoi
phai thong » phap thong, phai tuong, phan thong
thieu tuc » hieu tuc, thu tuc, thien tu
khoa khau » khoa kham, khoa phau, khoa chau
sach tham » sach nha
tham thuc » nham thuc, pham thuc, tam thuc
thuc cach » thuoc sach, truoc cach, thuc hanh
cac khoa » cac khoan, cac khoi, dac khoa
su sach » so sach, vu sach
tuc cac » tu cac, tich cac
tu sach » thu sach, te sach, tu cach

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( su sach thieu tuc cac khoa khau thong ) or ( tu sach tham thuc cach khoan phai thong ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( su sach thieu tuc cac khoa khau thong ) OR ( tu sach tham thuc cach khoan phai thong )).
• Adding a wildcard symbol may retrieve word variants: (( su sach thieu tuc cac khoa khau thong ) or ( tu sach tham thuc cach khoan phai thong ))*.