Perhaps you should try some spelling variations:
thanh van » thanh san, thanh toan, thanh phan
thu sach » tu sach, thuat sach, thuoc sach
va thanh » gia thanh, ban thanh, va tinh
ly quang » le quang, vu quang
van cua » vang cua, ban cua, dan cua
cua tre » cua te, cuu tre, cua triet
ve cac » va cac, vien cac
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 ((ly hang) OR (ly quang)) xa hoi. hieu ((ve cam) or (ve cac)) tu va thanh van cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ((ly hang) OR (ly quang)) xa hoi. hieu ((ve cam) OR (ve cac)) tu va thanh van cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ((ly hang) OR (ly quang)) xa hoi. hieu ((ve cam) or (ve cac)) tu va thanh van cua tre".
• Adding a wildcard symbol may retrieve word variants: thu sach ((ly hang) OR (ly quang)) xa hoi. hieu ((ve cam) or (ve cac)) tu va thanh van cua tre*.