Perhaps you should try some spelling variations:
nhanh hung » thanh hung, nhanh hong, nhanh chuong
hoa nhanh » hoc nhanh, hoa thanh, hoa khanh
sach hoc » cach hoc, sach hoi, mach hoc
cuu cong » cua cong, thu cong, cac cong
cong hoa » dong hoa, dong hoc, hang hoa
hung hoc » chung hoc, khung hoc, nhung hoc
cac thoi » cac toi, cac hop, cac tro
tu sach » thu sach, su sach, te sach
mai hoi » mai khoi, dai hoi, lai hoi
va dinh » van dinh, va kinh, va tinh

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach hoc tap, nghien cuu cong hoa nhanh hung hoc ((mai hoi) or (cac thoi)) va dinh so~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach hoc tap, nghien cuu cong hoa nhanh hung hoc ((mai hoi) OR (cac thoi)) va dinh so.
• Adding a wildcard symbol may retrieve word variants: tu sach hoc tap, nghien cuu cong hoa nhanh hung hoc ((mai hoi) or (cac thoi)) va dinh so*.