Perhaps you should try some spelling variations:
kham thong » khap thong, khau thong, pham thuong
phan tong » phan trong, phan cong, han tong
hoat phan » hoa phan, thuat phan, hoc phan
sach tham » sach nha
sach khoa » bach khoa, sach nha, anh khoa
khoa kham » kho khan, khoa than
sach dao » lanh dao
dao thuc » dan thuc, dao tuc, do thuc
thuc cac » thuc cach, tuc cac, phuc cac
cac hoat » cao hoat, cac khoan, cac thuat
tham hoc » thai hoc, tham hoa, than hoc
hoc sach » hoc sinh, hoc cac, hoc 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 dao thuc cac hoat phan tong ) or ( tu sach tham hoc sach khoa kham thong ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tu sach dao thuc cac hoat phan tong ) OR ( tu sach tham hoc sach khoa kham thong )).
• Adding a wildcard symbol may retrieve word variants: (( tu sach dao thuc cac hoat phan tong ) or ( tu sach tham hoc sach khoa kham thong ))*.