Perhaps you should try some spelling variations:
dinh tri » chinh tri
tu sach » thu sach, su sach, te sach
sach ty » sach y, sach tu, sach thu
ty lang » tay lang, ty xang, ty hang
lang xa » lang ha, dang xay, lang van
hieu va » hieu qua
cac hoc » cach hoc, cac hop, bac hoc
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 sach ty lang xa hoi. ((hieu va) or (lieu va)) cac hoc va ((dinh thi) OR (dinh tri)) cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty lang xa hoi. ((hieu va) OR (lieu va)) cac hoc va ((dinh thi) OR (dinh tri)) cua tu.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ty lang xa hoi. ((hieu va) or (lieu va)) cac hoc va ((dinh thi) OR (dinh tri)) cua tu".
• Adding a wildcard symbol may retrieve word variants: tu sach ty lang xa hoi. ((hieu va) or (lieu va)) cac hoc va ((dinh thi) OR (dinh tri)) cua tu*.