Perhaps you should try some spelling variations:
thanh lap » thanh san, phan lap, thanh hai
hieu van » hieu va, thien van, lieu va
tu sach » thu sach, su sach, te sach
duc van » duc va, duc tan, duc manh
han tai » hang tai, nhan tai, van tai
cam duc » cam xuc, cao duc, pham duc
van cam » van nam, van lam, van cau
ty lang » tay lang, ty hang, tu lang
cua tre » cua te, cuu tre, cua triet

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 ((ty lang) OR (ty xang)) xa hoi. hieu van cam duc van ((thanh lap) or (han tai)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((ty lang) OR (ty xang)) xa hoi. hieu van cam duc van ((thanh lap) OR (han tai)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((ty lang) OR (ty xang)) xa hoi. hieu van cam duc van ((thanh lap) or (han tai)) cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ((ty lang) OR (ty xang)) xa hoi. hieu van cam duc van ((thanh lap) or (han tai)) cua tre*.