Perhaps you should try some spelling variations:
cach khoan » cac khoan, cach hoan, bach khoa
thuc cach » thuoc sach, truoc cach, thuc hanh
khoan pho » khoan nhoi, khoan phai, khoan hoi
pho thong » he thong
phu thong » phap thong, khau thong, phan thong
sach dao » lanh dao
dao thuc » dan thuc, dao tuc, do thuc
pha thuc » phap thuc, pham thuc, phan thuc
thuc cac » tuc cac, phuc cac, thac cac
cac khoa » cac khoan, cac khoi, dac khoa
khoa phu » khoa phau, khoa thu, hoa phu
tu sach » thu sach, su sach, te sach
tu cach » tu cac

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 dao thuc cach khoan pho thong ) or ( tu cach pha thuc cac khoa phu thong ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tu sach dao thuc cach khoan pho thong ) OR ( tu cach pha thuc cac khoa phu thong )).
• Adding a wildcard symbol may retrieve word variants: (( tu sach dao thuc cach khoan pho thong ) or ( tu cach pha thuc cac khoa phu thong ))*.