Perhaps you should try some spelling variations:
cac cong » cua cong
hang hai » hoang hai, hang tai, thanh hai
hanh hai » thanh hai, nhanh hai, hanh tai
cong ban » cong bang, cong san, cong tan
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va, hieu van
nang xa » nang x, lang xa, nang ma
ve cac » va cac, vien cac
sai ky » sac 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: te ((sach ky) or (sai ky)) nang xa hoi. hieu ve cac cong ban ((hanh hai) OR (hang hai)) cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te ((sach ky) OR (sai ky)) nang xa hoi. hieu ve cac cong ban ((hanh hai) OR (hang hai)) cua tu*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te ((sach ky) or (sai ky)) nang xa hoi. hieu ve cac cong ban ((hanh hai) OR (hang hai)) cua tu*".