Perhaps you should try some spelling variations:
doanh thuong » doan phuong, anh thuong, dinh thuong
doanh tuong » doanh tong, doanh trong, doan cuong
nghien thu » nghiem thuc, nghiep thuc, nghien cuu
sach phoi » sach hoi, cach thoi, sach doi
phoi tai » phi tai, pham tai, hoc tai
cong hoa » dong hoa, dong hoc, hang hoa
tai toan » bai toan, tap toan, tai tuan
toan tai » toan tap, doanh tai, toan ban
su sach » so sach, vu sach
hoi tai » hoc tai, hoi trac
hoc xa » hoc ma

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 phoi tai, nghien thu cong hoa ((doanh tuong) OR (doanh thuong)) hoc xa hoi tai toan tai~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach phoi tai, nghien thu cong hoa ((doanh tuong) OR (doanh thuong)) hoc xa hoi tai toan tai".
• Adding a wildcard symbol may retrieve word variants: su sach phoi tai, nghien thu cong hoa ((doanh tuong) OR (doanh thuong)) hoc xa hoi tai toan tai*.