Perhaps you should try some spelling variations:
hang cong » dang cong, hang nong, bang cong
ban hang » ngan hang
cong hoc » dong hoc, cong hoa, cong coc
tan luan » tang luan, toan luan, dan luan
tu sach » thu sach, su sach, te sach
hoc tai » hoc dai, hoc tap, hoc bai
cuu mon » cuu mo, cuu mot, cuu cong
mon ban » mong ban, mon bao, con ban
hai tan » hai van, hai quan
ma hai » ta hai, va hai, xa hai

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 ((hoi dap) or (hoc tai)), nghien cuu mon ban hang cong hoc ma hai tan luan van~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((hoi dap) OR (hoc tai)), nghien cuu mon ban hang cong hoc ma hai tan luan van.
• Adding a wildcard symbol may retrieve word variants: tu sach ((hoi dap) or (hoc tai)), nghien cuu mon ban hang cong hoc ma hai tan luan van*.