Perhaps you should try some spelling variations:
doc tinh » doc trinh, dac tinh, loc tinh
tinh hoc » sinh hoc, tin hoc, hinh hoc
san khoa » toan khoa, hang khoa, da khoa
khoa hoc » hoa hoc
nhan tai » van tai, toan tai
hang tai » hang va, dung tai
cuu mot » cua mot, cuu mo, huu mot
mot hoc » mon hoc, mo hoc, mot goc
hoc san » hoc dan, toc san, hoc can
hoc xa » hoc ma
hoi ca » hoi cua, hoi cac, hoi cau

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

• Performing a fuzzy search may retrieve terms with similar spellings: doc tinh hoc tap, nghien cuu mot hoc san khoa hoc xa hoi ca ((nhan tai) or (hang tai))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc tinh hoc tap, nghien cuu mot hoc san khoa hoc xa hoi ca ((nhan tai) OR (hang tai)).
• Adding a wildcard symbol may retrieve word variants: doc tinh hoc tap, nghien cuu mot hoc san khoa hoc xa hoi ca ((nhan tai) or (hang tai))*.