Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
so sanh » do sanh
ve cham » va cham, ve chat, vu cham
nang ma » sang ma, nang cao, mang may
hanh di » hanh vi, hanh de, hang di
tang ma » mang may, tang van
sanh va » hanh va, anh va, sinh va
tuc van » thuc van, truc van, tuc va
di cua » dai cua, doi cua, de cua
ve cam » ve cac, va cam, ve cai
cua tu » cua tuc, cua su, cua cu

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 va ((nang ma) or (tang ma)) hoi. hieu ((ve cam) OR (ve cham)) tuc van hanh di cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sanh va ((nang ma) OR (tang ma)) hoi. hieu ((ve cam) OR (ve cham)) tuc van hanh di cua tu.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sanh va ((nang ma) or (tang ma)) hoi. hieu ((ve cam) OR (ve cham)) tuc van hanh di cua tu".
• Adding a wildcard symbol may retrieve word variants: so sanh va ((nang ma) or (tang ma)) hoi. hieu ((ve cam) OR (ve cham)) tuc van hanh di cua tu*.