Perhaps you should try some spelling variations:
thanh phan » thanh pho, thanh san, thanh toan
khong hoc » thong hoc, khong thuoc, khong chuc
khung hoc » chung hoc, nhung hoc, thuong hoc
dan thanh » dang thanh, danh thanh, ban thanh
benh hoc » sinh hoc
hoc phan » hoc dan, hoc pho
tu benh » tru benh, thu benh, tuy benh
cuu mot » cua mot, cuu mo, huu mot
mot hoc » mon hoc, mo hoc, mot goc
mai hoi » mai khoi, dai hoi, lai hoi
hoi dan » hoa dan, hoc dan, hoi dap

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu benh hoc tap, nghien cuu mot hoc phan ((khong hoc) or (khung hoc)) mai hoi dan thanh phan~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu benh hoc tap, nghien cuu mot hoc phan ((khong hoc) OR (khung hoc)) mai hoi dan thanh phan.
• Adding a wildcard symbol may retrieve word variants: tu benh hoc tap, nghien cuu mot hoc phan ((khong hoc) or (khung hoc)) mai hoi dan thanh phan*.