Perhaps you should try some spelling variations:
than thong » than thuong, toan thong, tran thong
sach tren » sach tien, sach tranh
tren chuc » tren thuc, treo chu
nang khoa » hang khoa, dang khoa, nang hoa
khoa than » khoa luan, hoa thai, hoa tan
khach tri » khach trai, khac trai, khanh tra
phu thong » pho thong, phap thong, khau thong
vu khach » vu khanh, vu khac, vay khach
benh hoa » benh khoa, benh hoc, benh ho
su sach » so sach, vu sach
tri tai » trinh tai
hoa phu » khoa phu, hoa phi, hoi phu

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 chuc nang khoa than thong ) or ( vu khach tri tai benh hoa phu thong ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( su sach tren chuc nang khoa than thong ) OR ( vu khach tri tai benh hoa phu thong )).
• Adding a wildcard symbol may retrieve word variants: (( su sach tren chuc nang khoa than thong ) or ( vu khach tri tai benh hoa phu thong ))*.