Perhaps you should try some spelling variations:
phan khong » phan hong, nhan khong, pham khong
khong hoc » khung hoc, thong hoc, khong thuoc
thanh hai » thanh phan, thanh hoa
hanh hoc » thanh hoc, hinh hoc, anh hoc
hoc phan » hoc dan, hoc pho
tu hanh » du hanh, lu hanh, thuc hanh
cuu mot » cua mot, cuu mo, huu mot
mot hoc » mon hoc, mo hoc, mot goc
hoc mai » hoc ma, hoc dai, hoc bai
mai hoi » mai khoi, dai hoi, lai hoi

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

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