Perhaps you should try some spelling variations:
dan khanh » dang khanh, van khanh, dat khanh
cuu thuc » cuu tac
dan hanh » dang hanh, dan thanh, ban hanh
hieu van » thien van, lieu va, hieu ve
nang xa » nang x, lang xa, nang ma
hieu va » lieu va, hieu qua
de cua » le cua, te cua, dieu cua
tu sac » tu sach, tu cac, tu san
sac ky » cac ky, sai ky
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: tu sac ky nang xa hoi. ((hieu van) OR (hieu va)) cuu thuc ((dan hanh) or (dan khanh)) de cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sac ky nang xa hoi. ((hieu van) OR (hieu va)) cuu thuc ((dan hanh) OR (dan khanh)) de cua tu.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sac ky nang xa hoi. ((hieu van) OR (hieu va)) cuu thuc ((dan hanh) or (dan khanh)) de cua tu".
• Adding a wildcard symbol may retrieve word variants: tu sac ky nang xa hoi. ((hieu van) OR (hieu va)) cuu thuc ((dan hanh) or (dan khanh)) de cua tu*.