Perhaps you should try some spelling variations:
nuoc quan » nuoc luan, quoc quan, nguoi quan
hieu van » hieu va, thien van, lieu va
nuoc san » nuoc luan, nguoi san, nuoc sach
benh vi » benh va, benh ve, benh li
van lam » van nam
lang ha » long ha
cua tre » cua te, cuu tre, cua triet
ha hoi » hoa hoi, ha noi, xa hoi
sac ky » cac ky, sai ky
vi cua » vai cua, di cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((sach y) or (sac ky)) lang ha hoi. hieu van lam ((nuoc san) or (nuoc quan)) benh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach y) OR (sac ky)) lang ha hoi. hieu van lam ((nuoc san) OR (nuoc quan)) benh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: tu ((sach y) or (sac ky)) lang ha hoi. hieu van lam ((nuoc san) or (nuoc quan)) benh vi cua tre*.