Perhaps you should try some spelling variations:
thong thuong » thong thong, hang thuong, cong thuong
thuong dan » huong dan, thuong han, thuong dam
hieu manh » chieu xanh, hieu nganh, dieu hanh
hiem ngan » kim ngan, viem gan
sinh cua » manh cua, dinh cuu
dan toan » van toan, dan than, manh toan
toan cau » toan cao, toan ban, toan tap
sinh va » sinh vat, tinh va, dinh van

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((hieu manh) or (hiem ngan)) - hanh ((sinh cua) OR (sinh va)) thong thuong dan toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hieu manh) OR (hiem ngan)) - hanh ((sinh cua) OR (sinh va)) thong thuong dan toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((hieu manh) or (hiem ngan)) - hanh ((sinh cua) OR (sinh va)) thong thuong dan toan cau".
• Adding a wildcard symbol may retrieve word variants: hoc ((hieu manh) or (hiem ngan)) - hanh ((sinh cua) OR (sinh va)) thong thuong dan toan cau*.