Perhaps you should try some spelling variations:
thanh chong » thanh chuong, thanh cong, nhanh chong
chong dich » luong dich, hang dich
nghien cac » nghiep cach, nghien cuu, nghiep cay
hoc thanh » hoc nhanh, hoan thanh, hoc phan
cong hoc » dong hoc, cong hoa, cong coc
cac cong » cua cong
sach hoc » cach hoc, sach hoi, mach hoc
dich can » dich han, dich ran, lich can
ca giang » cua giang, ha giang, ma giang
can hoi » cau hoi, can ho, dan hoi
ca gian » ca giao, va gian, ca gia
su sach » so sach, vu sach

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach hoc tap, nghien cac cong hoc thanh chong dich can hoi ((ca gian) OR (ca giang)) dan~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach hoc tap, nghien cac cong hoc thanh chong dich can hoi ((ca gian) OR (ca giang)) dan".
• Adding a wildcard symbol may retrieve word variants: su sach hoc tap, nghien cac cong hoc thanh chong dich can hoi ((ca gian) OR (ca giang)) dan*.