Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
cua triet » cua viet, su triet, va triet
sang xa » song xa, lang xa, sang ma
hieu ve » hieu va, hieu van
cac luu » cac luat, sach luu
luu van » cuu van, luan van, luu hanh
hanh va » hang va
cua tre » cua te, cuu tre, dua tren
ve cac » va cac, vien cac

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuat sach _ sang xa hoi. hieu ve cac luu van ((hanh va) or (hanh vi)) ((cua tre) OR (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuat sach _ sang xa hoi. hieu ve cac luu van ((hanh va) OR (hanh vi)) ((cua tre) OR (cua triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuat sach _ sang xa hoi. hieu ve cac luu van ((hanh va) or (hanh vi)) ((cua tre) OR (cua triet))".
• Adding a wildcard symbol may retrieve word variants: thuat sach _ sang xa hoi. hieu ve cac luu van ((hanh va) or (hanh vi)) ((cua tre) OR (cua triet))*.