Perhaps you should try some spelling variations:
tay quang » tac quang, tai quang, tao quang
tay lang » tai lang, tay tang, tham lang
doan hai » doanh tai, hoang hai, doan va
tu sach » thu sach, su sach, te sach
dan hai » dang hai, dan khai, van hai
cua tre » cua te, cuu tre, cua triet
truc va » thuc va, thuc vat, trung va
hieu va » lieu va, hieu qua
va cau » van cau, va cac, va dau

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 ((tay lang) or (tay quang)) xa hoi. hieu va cau truc va ((dan hai) OR (doan hai)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((tay lang) OR (tay quang)) xa hoi. hieu va cau truc va ((dan hai) OR (doan hai)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((tay lang) or (tay quang)) xa hoi. hieu va cau truc va ((dan hai) OR (doan hai)) cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ((tay lang) or (tay quang)) xa hoi. hieu va cau truc va ((dan hai) OR (doan hai)) cua tre*.