Perhaps you should try some spelling variations:
tieu cao » kieu cao, lieu cao, sieu cao
khoa hoc » hoa hoc
hoc tieu » hoc thieu, hoc dieu, hoc sieu
tu manh » tu minh, tu hanh, tung manh
cao cua » ca cua, co cua, cau cua
vu manh » vu minh, vu anh, suc manh
dan so » dan soc, dan su, dan mo
con so » cong so, hon so, con bo

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu manh) OR (vu manh)) khoa hoc tieu cao cua ets : nhung ((dan so) or (con so)) vat đai~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu manh) OR (vu manh)) khoa hoc tieu cao cua ets : nhung ((dan so) OR (con so)) vat đai.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu manh) OR (vu manh)) khoa hoc tieu cao cua ets : nhung ((dan so) or (con so)) vat đai".
• Adding a wildcard symbol may retrieve word variants: ((tu manh) OR (vu manh)) khoa hoc tieu cao cua ets : nhung ((dan so) or (con so)) vat đai*.