Perhaps you should try some spelling variations:
sach tham » sach nha
hieu viec » nhieu viec, hieu ve, sieu viet
viec dat » vien dai, vien da, viec lam
dang mat » dang vat, dang mau, dung mat
sach thu » sach thue, sach thieu, cach thuc
hanh va » hang va, hanh vi
va hanh » van hanh, va thanh, va danh
dat xuc » dat nuoc, dat duoc, chat xuc
dang ma » dang mau, dang mam, tang ma
xuc va » duc va, tuc va, luc va
o viet » so viet, hoc viet
va o » va co, va do, va mo

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc ((sach thu) OR (sach tham)) ((dang ma) or (dang mat)) hoi. hieu viec dat xuc va hanh va o viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc ((sach thu) OR (sach tham)) ((dang ma) OR (dang mat)) hoi. hieu viec dat xuc va hanh va o viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc ((sach thu) OR (sach tham)) ((dang ma) or (dang mat)) hoi. hieu viec dat xuc va hanh va o viet".
• Adding a wildcard symbol may retrieve word variants: toc ((sach thu) OR (sach tham)) ((dang ma) or (dang mat)) hoi. hieu viec dat xuc va hanh va o viet*.