Perhaps you should try some spelling variations:
thuat mach » thuat sach, thuat tach, thuyet mach
mach khoan » cac khoan, bach khoa, mach phan
khoan nhoi » khoan hoi, khoa hoi, khoa noi
thuy doanh » thuy oanh, thuy anh, thu oanh
doanh khoa » toan khoa
phau thong » phap thong, khau thong, phan thong
dai thuat » dai thua, giai thuat, ki thuat
nhoi cong » noi cong, nguoi cong, ngoai cong
khoa phau » hoa phan, khoa kham, khoa than
cach dai » cac dai, cac dan, cac bai
sach dao » lanh dao
dao thuy » do thuy, dao huy, dang thuy
tu cach » tu cac
te sach » toc sach

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( tu cach dai thuat mach khoan nhoi cong ) or ( te sach dao thuy doanh khoa phau thong ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tu cach dai thuat mach khoan nhoi cong ) OR ( te sach dao thuy doanh khoa phau thong )).
• Adding a wildcard symbol may retrieve word variants: (( tu cach dai thuat mach khoan nhoi cong ) or ( te sach dao thuy doanh khoa phau thong ))*.