Perhaps you should try some spelling variations:
cach khoan » cac khoan, cach hoan, bach khoa
khoan khoa » khuan khoa, khoa khoa, toan khoa
khoa thong » hoa thong, thoai thong, khoi khong
thuc cach » thuoc sach, truoc cach, thuc hanh
pho thong » he thong
sanh bai » sach bai, anh bai, san bai
bai thuc » bai thuoc, bao thuc, dai thuc
sach tri » sach tai, sach tren, sach truc
tri phuc » tri thuc, tri phu, thi phuc
phuc anh » phuc thanh, phuc khanh, thuc hanh
anh khoa » doanh khoa, hang khoa
khoa pho » khoa phu, khoa khoa, khoa phau
so sanh » do sanh
su sach » so sach, vu sach

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( so sanh bai thuc cach khoan khoa thong ) or ( su sach tri phuc anh khoa pho thong ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( so sanh bai thuc cach khoan khoa thong ) OR ( su sach tri phuc anh khoa pho thong )).
• Adding a wildcard symbol may retrieve word variants: (( so sanh bai thuc cach khoan khoa thong ) or ( su sach tri phuc anh khoa pho thong ))*.