Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
cau nuoc » cap nuoc, cac nuoc, dau nuoc
tu sach » thu sach, su sach, te sach
sach ty » sach y, sach tu, sach thu
van cau » van dau, van hau, van chat
ty ang » ty xang, ty hang, ty anh
ang xa » lang xa, mang xa, dang xay
cua tu » cua tuc, cua cu, cua te
cua su » qua su

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 ang xa hoi. hieu van cau nuoc ((va tinh) or (may tinh)) vi ((cua tu) OR (cua su))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty ang xa hoi. hieu van cau nuoc ((va tinh) OR (may tinh)) vi ((cua tu) OR (cua su)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ty ang xa hoi. hieu van cau nuoc ((va tinh) or (may tinh)) vi ((cua tu) OR (cua su))".
• Adding a wildcard symbol may retrieve word variants: tu sach ty ang xa hoi. hieu van cau nuoc ((va tinh) or (may tinh)) vi ((cua tu) OR (cua su))*.