Perhaps you should try some spelling variations:
hanh trinh » canh tranh, hanh chinh
hanh khoa » hang khoa, anh khoa, hanh hoa
pho thong » he thong
trinh duc » tinh duc, trinh doc, trinh dung
khoan han » khoan thanh, khoan danh, khoan phai
sach bai » sach dao, cac bai, sach xa
bai thuc » bai thuoc, bao thuc, dai thuc
khoa pho » khoa phu, khoa khoa, khoa phau
te sach » toc sach
vu hanh » vu khanh, vu thanh, du hanh
duc cac » duoc cac, tuc cac, muc cac
tong » cong, dong, song

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( te sach bai thuc hanh khoa pho thong ) or ( vu hanh trinh duc cac khoan han tong ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( te sach bai thuc hanh khoa pho thong ) OR ( vu hanh trinh duc cac khoan han tong )).
• Adding a wildcard symbol may retrieve word variants: (( te sach bai thuc hanh khoa pho thong ) or ( vu hanh trinh duc cac khoan han tong ))*.