Perhaps you should try some spelling variations:
nghien thu » nghiem thuc, nghiep thuc, nghien cuu
doanh khoa » toan khoa
hoa doanh » toan doanh, hoa dan
hoc sach » hoc sinh, hoc cac, hoc anh
thue tap » thuc tap, thue tai, hue tap
cong hoa » dong hoa, dong hoc, hang hoa
khoa hoc » hoa hoc
bai toan » bai tap
toan tai » toan tap, doanh tai, toan ban
te sach » toc sach
hoi bai » hoc bai, hoi tai, khoi bay
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: ((te sach) or (hoc sach)) thue tap, nghien thu cong hoa doanh khoa hoc xa hoi bai toan tai~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (hoc sach)) thue tap, nghien thu cong hoa doanh khoa hoc xa hoi bai toan tai.
• Adding a wildcard symbol may retrieve word variants: ((te sach) or (hoc sach)) thue tap, nghien thu cong hoa doanh khoa hoc xa hoi bai toan tai*.