Perhaps you should try some spelling variations:
nhanh hoan » thanh hoang, thanh hoa, khanh hoa
nhanh hoa » thanh hoa, khanh hoa, nhanh ha
sach hoc » cach hoc, sach hoi, mach hoc
cuu dong » cuu cong, cuu tong, cuu long
dong hoc » dong co, dong luc
su sach » so sach, vu sach
dap tan » dac tan, dai tan, tap toan
tan tai » toan tai, tang tai, tuan tai
hoc xa » hoc ma

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 hoc tap, nghien cuu dong hoc ((nhanh hoa) or (nhanh hoan)) hoc xa hoi dap tan tai~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach hoc tap, nghien cuu dong hoc ((nhanh hoa) OR (nhanh hoan)) hoc xa hoi dap tan tai.
• Adding a wildcard symbol may retrieve word variants: su sach hoc tap, nghien cuu dong hoc ((nhanh hoa) or (nhanh hoan)) hoc xa hoi dap tan tai*.