Perhaps you should try some spelling variations:
nghien cua » nghien cuu, nghiep cua, nghiep vua
hanh tung » thanh tung, manh tung, hanh dung
danh nhan » doanh nhan, thanh nhan, benh nhan
van thanh » ban thanh, van tuan
sach hoi » sach doi, sach moi, cach thoi
hoc hanh » hoc nhanh, hoc thanh, hoc anh
tung hoc » trung hoc, tuong hoc, dung hoc
su sach » so sach, vu sach
hoi tap » hoi dap, hoi tai, hai tap
mot hoc » mon hoc, mo hoc, mot goc
tap hai » tap bai, tap dai, tai hai

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 hoi tap, nghien cua mot hoc hanh tung hoc tap hai ((danh nhan) or (van thanh)) van~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach hoi tap, nghien cua mot hoc hanh tung hoc tap hai ((danh nhan) OR (van thanh)) van.
• Adding a wildcard symbol may retrieve word variants: su sach hoi tap, nghien cua mot hoc hanh tung hoc tap hai ((danh nhan) or (van thanh)) van*.