Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
nghien cac » nghiep cach, nghien cuu, nghiep cay
doanh khoa » toan khoa
hoc doanh » hoa doanh, hoc danh, hoc dan
thu sach » tu sach, thuoc sach, thu hoach
cac cong » cua cong
cong hoc » dong hoc, cong hoa, cong coc
khoa hoc » hoa hoc
hoa benh » khoa benh, hoa binh, hoc benh
nhan va » nhan tai, nhan dan, nhan tao

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((thu sach) OR (thuat sach)) hoc tap, nghien cac cong hoc doanh khoa hoc ma hoa benh nhan va~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((thu sach) OR (thuat sach)) hoc tap, nghien cac cong hoc doanh khoa hoc ma hoa benh nhan va".
• Adding a wildcard symbol may retrieve word variants: ((thu sach) OR (thuat sach)) hoc tap, nghien cac cong hoc doanh khoa hoc ma hoa benh nhan va*.