Perhaps you should try some spelling variations:
hach hoc » cach hoc, mach hoc, hoach hoi
khoa hoc » hoa hoc
cua sinh » hoa sinh, va sinh
sinh van » sinh vat, dinh van, sinh va
tu hach » tu hanh, tu cach, tu sach
cuu mot » cua mot, huu mot, cuu vuot
hoa cua » hoa chat, hoa xuat
hoc da » hoc dan, hoc dai, hoc dat
hoc xa » hoc ma
xa hoa » xa khoa, xa hoi, ma hoa

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu hach hoc tap, nghien ((cuu mot) or (cuu mo)) hoc da khoa hoc xa hoa cua sinh van~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu hach hoc tap, nghien ((cuu mot) OR (cuu mo)) hoc da khoa hoc xa hoa cua sinh van.
• Adding a wildcard symbol may retrieve word variants: tu hach hoc tap, nghien ((cuu mot) or (cuu mo)) hoc da khoa hoc xa hoa cua sinh van*.