Perhaps you should try some spelling variations:
khoa sach » hoc sach
gian dang » gian dan, gian lang, gian dong
sach luan » sach luyen, sach han, san luan
trien chi » trien thi, trien khai, trieu thi
luan tieu » luan thiet
tieu tri » dieu tri, sieu tri, tien tri
pho sach » pham sach, khoe sach, pho trach
tieu tra » dieu tra, tieu tham, dieu tri
pham lan » pham luan, pham van, phan lan
pham san » pham van, pha san, pham can
gian don » gian dan, giang son, gian dien
tiep cua » tiep can, dieu cua, tap cua
cac qua » cau qua, tac quan
cap qua » cau qua, cay qua, tap quan

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: (( pho ((gian dang) OR (gian don)) trien chi ) OR ((( pho ((cap qua) OR (cac qua)) tiep cua ) OR ((( ((pham san) OR (pham lan)) luan tieu tra ) OR ((( pho sach luan tieu tri ) OR ( khoa sach luan tieu tri ))))))))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( pho ((gian dang) or (gian don)) trien chi ) or ((( pho ((cap qua) OR (cac qua)) tiep cua ) or ((( ((pham san) or (pham lan)) luan tieu tra ) or ((( pho sach luan tieu tri ) or ( khoa sach luan tieu tri ))))))))~".
• Adding a wildcard symbol may retrieve word variants: (( pho ((gian dang) or (gian don)) trien chi ) or ((( pho ((cap qua) OR (cac qua)) tiep cua ) or ((( ((pham san) or (pham lan)) luan tieu tra ) or ((( pho sach luan tieu tri ) or ( khoa sach luan tieu tri ))))))))*.