Perhaps you should try some spelling variations:
khan thong » khap thong, khau thong, nhan thong
thuoc sach » hoc sach, nuoc sach, thuat sach
phau thong » phap thong, khau thong, phan thong
tac thuoc » tao thuoc, truc thuoc, tac thuong
hanh khoa » hang khoa, anh khoa, hanh hoa
khoa phau » hoa phan, khoa kham, khoa than
sach tac » sach bac, sach tai, sach tham
sach kho » bach khoa, sach dao, sach nha
kho khan » khoa kham, khoa than
sach tri » sach tai, sach tren, sach truc
tue hanh » tu hanh, tuc hanh, tue anh
tu sach » thu sach, su sach, te 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 sach tac thuoc sach kho khan thong ) or ( tu sach tri tue hanh khoa phau thong ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tu sach tac thuoc sach kho khan thong ) OR ( tu sach tri tue hanh khoa phau thong )).
• Adding a wildcard symbol may retrieve word variants: (( tu sach tac thuoc sach kho khan thong ) or ( tu sach tri tue hanh khoa phau thong ))*.