Perhaps you should try some spelling variations:
sach trien » sach tien, sach thieu, cach thien
trien thuc » trien thuoc, trien thuat, kien thuc
khoa thong » hoa thong, thoai thong, pho thong
khoan phai » khong phai, khoa phau, khoan hoi
phai thong » phap thong, phai tuong, phan thong
hanh khoa » hang khoa, anh khoa, hanh hoa
sach tren » sach tien, sach tranh
tren thuc » tron thuc, trinh thuc, trong thuc
thuc cac » thuc cach, tuc cac, phuc cac
so sach » so sanh, bo sach, co sach
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: (( so sach trien thuc hanh khoa thong thong ) or ( te sach tren thuc cac khoan phai thong ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( so sach trien thuc hanh khoa thong thong ) OR ( te sach tren thuc cac khoan phai thong )).
• Adding a wildcard symbol may retrieve word variants: (( so sach trien thuc hanh khoa thong thong ) or ( te sach tren thuc cac khoan phai thong ))*.