Perhaps you should try some spelling variations:
tham luc » than luc, tham nuoc, tham thuc
van hanh » van thanh, ban hanh, van ban
va triet » va thiet, va trien, ve triet
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
hieu va » hieu qua
van anh » van thanh, tuan anh, van minh
vi va » vi van, vai va, vu va

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach ky nang xa hoi. ((hieu va) OR (lieu va)) tham luc ((van hanh) or (van anh)) vi va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang xa hoi. ((hieu va) OR (lieu va)) tham luc ((van hanh) OR (van anh)) vi va triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang xa hoi. ((hieu va) OR (lieu va)) tham luc ((van hanh) or (van anh)) vi va triet".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang xa hoi. ((hieu va) OR (lieu va)) tham luc ((van hanh) or (van anh)) vi va triet*.