Perhaps you should try some spelling variations:
khoan phai » khong phai, khoa phau, khoan hoi
phai thong » phap thong, phai tuong, phan thong
phu thong » pho thong, phap thong, khau thong
hang khoa » dung khoa
dan khoan » dan khoa, dai khoang, toan khoan
thi hang » thi hanh, thi nang, thi hong
khoa phu » khoa phau, khoa thu, hoa phu
bai thuc » bai thuoc, bao thuc, dai thuc
thuc dan » thuc hanh, hoc dan, thuc vat
tu sach » thu sach, su sach, te sach
sach xa » sach dao, sach nha, sach bai
can bai » can ban, cac bai, can dai
xa thi » xa thai, ha thi, ta thi
su can » su van, su cao, tu can

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 xa thi hang khoa phu thong ) or ( su can bai thuc dan khoan phai thong ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tu sach xa thi hang khoa phu thong ) OR ( su can bai thuc dan khoan phai thong )).
• Adding a wildcard symbol may retrieve word variants: (( tu sach xa thi hang khoa phu thong ) or ( su can bai thuc dan khoan phai thong ))*.