Perhaps you should try some spelling variations:
hoang hai » hoang thi, hoang van
va triet » va thiet, va trien, ve triet
thuc dan » thuc hanh, hoc dan, thuc vat
hang hai » hang tai, thanh hai, hang va
nam thuc » nam thuoc, am thuc, nam thu
hieu va » lieu va, hieu qua
sach ky » sac ky, sach y, sach ty
hieu ve » hieu van
nang xa » nang x, lang xa, nang ma
vu sach » vu bach, su sach, vu khach

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

• Performing a fuzzy search may retrieve terms with similar spellings: vu sach ky nang xa hoi. ((hieu ve) or (hieu va)) nam thuc dan ((hang hai) OR (hoang hai)) va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach ky nang xa hoi. ((hieu ve) OR (hieu va)) nam thuc dan ((hang hai) OR (hoang hai)) va triet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu sach ky nang xa hoi. ((hieu ve) or (hieu va)) nam thuc dan ((hang hai) OR (hoang hai)) va triet*".