Perhaps you should try some spelling variations:
nghien thu » nghiem thuc, nghiep thuc, nghien cuu
hoc doanh » hoa doanh, hoc danh, hoc dan
doanh hoa » doanh khoa, doanh hoan, danh hoa
thu sach » thuat sach, thuoc sach, thu hoach
toi gian » thoi gian, thi giang, don gian
cong hoc » dong hoc, cong hoa, cong coc
phan dau » phan tu, hang dau
tu sach » su sach, te sach, tu cach
xa phan » va phan, a phan, x phan

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) OR (thu sach)) toi gian, nghien thu cong hoc doanh hoa hoc ma hoa xa phan dau~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) OR (thu sach)) toi gian, nghien thu cong hoc doanh hoa hoc ma hoa xa phan dau".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) OR (thu sach)) toi gian, nghien thu cong hoc doanh hoa hoc ma hoa xa phan dau*.