Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
hanh dai » hanh tai, hanh dao, vanh dai
nang xa » lang xa, nang ma, mang xa
van cac » van hac, van cau, van bac
cac lop » cac hop, cac loai
va hanh » van hanh, va thanh, va danh
tu sac » tu sach, tu cac, tu san
sac ky » cac ky, sai ky
lop va » lap va, hop va, nop va
cua te » cua tu

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sac ky ((nang xa) or (nang x)) hoi. hieu van cac lop va hanh dai cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sac ky ((nang xa) OR (nang x)) hoi. hieu van cac lop va hanh dai cua te.
• Adding a wildcard symbol may retrieve word variants: tu sac ky ((nang xa) or (nang x)) hoi. hieu van cac lop va hanh dai cua te*.