Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
doan hai » doanh tai, hoang hai, doan va
cua viet » ca viet, hoa viet, cua vat
ky dang » ky danh
cac tuc » cac toc, cac tu, cac tac
dan hai » dang hai, dan khai, van hai
tuc va » thuc va, truc va, tuc xa

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 ((ky dang) or (ky nang)) xa hoi. lieu va cac tuc va ((dan hai) OR (doan hai)) cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ((ky dang) OR (ky nang)) xa hoi. lieu va cac tuc va ((dan hai) OR (doan hai)) cua viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ((ky dang) or (ky nang)) xa hoi. lieu va cac tuc va ((dan hai) OR (doan hai)) cua viet".
• Adding a wildcard symbol may retrieve word variants: thu sach ((ky dang) or (ky nang)) xa hoi. lieu va cac tuc va ((dan hai) OR (doan hai)) cua viet*.