Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
thanh dai » thanh hai, thanh tai, thanh dat
thu sach » tu sach, thuoc sach, thu hoach
va thanh » gia thanh, ban thanh, va tinh
cua viet » ca viet, hoa viet, cua vat
xay hoi » xa hoi, tay hoi, cay phoi
ty van » ly van, ta van
ve cac » va cac, vien cac
luc va » duc va, tuc va, loc va
ve cam » ve cham, va cam, ve cai

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((thu sach) or (thuat sach)) ty van xay hoi. hieu ((ve cam) OR (ve cac)) luc va thanh dai cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((thu sach) OR (thuat sach)) ty van xay hoi. hieu ((ve cam) OR (ve cac)) luc va thanh dai cua viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((thu sach) or (thuat sach)) ty van xay hoi. hieu ((ve cam) OR (ve cac)) luc va thanh dai cua viet".
• Adding a wildcard symbol may retrieve word variants: ((thu sach) or (thuat sach)) ty van xay hoi. hieu ((ve cam) OR (ve cac)) luc va thanh dai cua viet*.