Perhaps you should try some spelling variations:
sach hoc » cach hoc, sach hoi, mach hoc
pho cong » pho uong, cho cong, pho dong
cong coc » cong cuoc, cong cac, cong co
gian dan » gian lang
te sach » toc sach
cuu mon » cuu mo, cuu mot, cuu cong
mon hoc » toan hoc, dong hoc
nhan va » nhan tai, nhan dan, nhan tao
coc xa » hoc xa, cac xa, coc ha

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach hoc tap, nghien cuu mon hoc pho cong coc xa hoi va ((gian dan) or (nhan va))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach hoc tap, nghien cuu mon hoc pho cong coc xa hoi va ((gian dan) OR (nhan va)).
• Adding a wildcard symbol may retrieve word variants: te sach hoc tap, nghien cuu mon hoc pho cong coc xa hoi va ((gian dan) or (nhan va))*.