Perhaps you should try some spelling variations:
thong cong » trong cong, tong cong, thong thong
tien manh » tien anh, tien thanh, tieng anh
hoc tien » hoc tieng, hoc hien, hoc vien
trinh ve » trinh va, trinh vi, trinh viet
trinh he » trinh han, trinh hoa, trinh thi
cong bai » cuong bai, cong hai, cung bai
bai toan » bai tap
toan cau » toan cao, toan ban, toan tap

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc tien manh - hanh ((trinh ve) or (trinh he)) thong cong bai toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc tien manh - hanh ((trinh ve) OR (trinh he)) thong cong bai toan cau.
• Adding a wildcard symbol may retrieve word variants: hoc tien manh - hanh ((trinh ve) or (trinh he)) thong cong bai toan cau*.