Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
nang cai » nang tai, nang cap, nang can
so sanh » do sanh
luc ban » duc ban, cuc ban, luc bat
cac luc » cau luc, coc luc, cac nuoc
qua cac » cua cac
sanh y » sinh y, anh y, hanh y
vi cua » vai cua
di cua » dai cua, doi cua, de cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sanh y ((nang cai) or (nang cao)) hoi. hieu qua cac luc ban thanh ((vi cua) OR (di cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sanh y ((nang cai) OR (nang cao)) hoi. hieu qua cac luc ban thanh ((vi cua) OR (di cua)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sanh y ((nang cai) or (nang cao)) hoi. hieu qua cac luc ban thanh ((vi cua) OR (di cua)) tre".
• Adding a wildcard symbol may retrieve word variants: so sanh y ((nang cai) or (nang cao)) hoi. hieu qua cac luc ban thanh ((vi cua) OR (di cua)) tre*.