Perhaps you should try some spelling variations:
khoan phai » khong phai, khoa phau, khoan hoi
cach khoan » cac khoan, cach hoan, bach khoa
phai thong » phap thong, phai tuong, phan thong
khach tri » khach trai, khac trai, khanh tra
hanh khoa » hang khoa, anh khoa, hanh hoa
cach thuc » anh thuc, cac thu
thuc thuc » hoc thuc
thuc cach » thuoc sach, truoc cach, tuc cac
vu khach » vu khanh, vu khac, vay khach
tri thuc » tri tue
khoa he » hoa he, khoa hoc, khong he
su cach » su sach, tu cach, su cac

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( vu khach tri thuc hanh khoa he thong ) or ( su cach thuc thuc cach khoan phai thong ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( vu khach tri thuc hanh khoa he thong ) OR ( su cach thuc thuc cach khoan phai thong )).
• Adding a wildcard symbol may retrieve word variants: (( vu khach tri thuc hanh khoa he thong ) or ( su cach thuc thuc cach khoan phai thong ))*.