Perhaps you should try some spelling variations:
kham thong » khap thong, khau thong, pham thuong
sach tren » sach tien, sach tranh
tren thuc » trien thuc, tron thuc, trinh thuc
dan trong » ban trong, dat trong, dao trong
khoa kham » kho khan, khoa than
thuc anh » thuc hanh, thuy anh, thu anh
sach tai » sach bai, sach tham, sach dao
tai thuc » thai thuc, tri thuc, dai thuc
anh khoa » doanh khoa, hang khoa
su sach » so sach, vu sach
anh hoc » sinh hoc, benh hoc, hinh hoc
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: (( su sach tren thuc anh hoc dan trong ) or ( te sach tai thuc anh khoa kham thong ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( su sach tren thuc anh hoc dan trong ) OR ( te sach tai thuc anh khoa kham thong )).
• Adding a wildcard symbol may retrieve word variants: (( su sach tren thuc anh hoc dan trong ) or ( te sach tai thuc anh khoa kham thong ))*.