Perhaps you should try some spelling variations:
sach hoi » sach doi, sach moi, cach thoi
hoc phan » hoc dan, hoc pho
phan pho » phan phoi, phan phuoc, thanh pho
gian dau » gian dan, gian dac, gia dau
su sach » so sach, vu sach
cuu mon » cuu mo, cuu mot, cuu cong
pho hoc » phoi hoc, cho hoc, pho ho
hoi dan » hoa dan, hoc dan, thoi dai
hoc xa » hoc ma

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: su sach hoi dap, nghien ((cuu mon) OR (cua mot)) hoc phan pho hoc xa hoi dan gian dau~.
• Adding a wildcard symbol may retrieve word variants: su sach hoi dap, nghien ((cuu mon) or (cua mot)) hoc phan pho hoc xa hoi dan gian dau*.