Perhaps you should try some spelling variations:
tien thuoc » trien thuoc, tin thuoc, bien thuoc
thuoc sinh » hoc sinh, thu sinh, thuoc sach
phu thong » pho thong, phap thong, khau thong
sach tien » sach tren, sach thieu
sinh khoa » sinh hoc, sinh hoat, anh khoa
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 thoi » cac toi, cac hop, cac tro
thoi phu » thi phu, hoi phu, thon phu
su sach » so sach, vu sach
khoa he » hoa he, khoa hoc, khong he

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 bai thuc cac thoi phu thong ) or ( su sach tien thuoc sinh khoa he thong ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( su sach bai thuc cac thoi phu thong ) OR ( su sach tien thuoc sinh khoa he thong )).
• Adding a wildcard symbol may retrieve word variants: (( su sach bai thuc cac thoi phu thong ) or ( su sach tien thuoc sinh khoa he thong ))*.