Perhaps you should try some spelling variations:
sach trien » sach tien, sach tren, sach thieu
trien thuc » trien thuoc, tren thuc, trien thuat
hanh chung » hanh nhung, lanh chung, thanh chuong
kham thong » khap thong, khau thong, pham thuong
khoa kham » kho khan, khoa than
chung ha » chung han, chung ta, hung ha
ha thong » hoa thong, nha thong, he thong
sach bai » sach dao, cac bai, sach xa
bai thuc » bai thuoc, bao thuc, dai thuc
thuc cac » thuc cach, tuc cac, phuc cac
cac khoa » cac khoan, cac khoi, dac khoa
tu sach » thu sach, te sach, tu cach
su sach » so sach, vu sach

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

• If you are trying to use Boolean operators, they must be ALL CAPS: (( tu sach trien thuc hanh chung ha thong ) OR ( su sach bai thuc cac khoa kham thong ))~.
• Adding a wildcard symbol may retrieve word variants: (( tu sach trien thuc hanh chung ha thong ) or ( su sach bai thuc cac khoa kham thong ))*.