Perhaps you should try some spelling variations:
tien thanh » tien thinh, tran thanh, den thanh
hien xanh » hien hanh, hien nhanh, chieu xanh
hanh tang » hanh trang, hanh mang, hanh tung
cua thong » cua thuong, cua khong, cua tong
thong bai » thong tai, nhung bai, thong xay
anh tang » anh bang, anh dang, anh nang
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 ((hien xanh) or (tien thanh)) - ((hanh tang) OR (anh tang)) cua thong thong bai toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hien xanh) OR (tien thanh)) - ((hanh tang) OR (anh tang)) cua thong thong bai toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((hien xanh) or (tien thanh)) - ((hanh tang) OR (anh tang)) cua thong thong bai toan cau".
• Adding a wildcard symbol may retrieve word variants: hoc ((hien xanh) or (tien thanh)) - ((hanh tang) OR (anh tang)) cua thong thong bai toan cau*.