Perhaps you should try some spelling variations:
thuc nguoi » toc nguoi
nguoi dao » nguoi tay
dao hanh » dao thanh, dang hanh, ban hanh
cua tuc » cua duc, cua tu, cua thuoc
cua tre » cua te, cuu tre, cua triet
hanh di » hanh vi, hanh de, hang di
ve thuc » va thuc
hieu ve » hieu va, hieu van
sac ky » sai ky
nang o » nang co, nang ho, nang ro
o hai » co hai, so hai, o lai

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

• Performing a fuzzy search may retrieve terms with similar spellings: su ((sac ky) OR (cac ky)) nang o hai. hieu ve thuc nguoi dao hanh di ((cua tre) or (cua tuc))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sac ky) OR (cac ky)) nang o hai. hieu ve thuc nguoi dao hanh di ((cua tre) OR (cua tuc))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sac ky) OR (cac ky)) nang o hai. hieu ve thuc nguoi dao hanh di ((cua tre) or (cua tuc))*".