Perhaps you should try some spelling variations:
cau tren » cu tren, dau tren, ca tren
hieu van » hieu va, thien van, lieu va
vai cau » va cau, van cau, vai cac
dan vai » dan va, dan tai, dan vat
te sach » toc sach
ky dang » ky nang, ky danh
ky lang » ky nang, ky tang, tay lang
tuc va » thuc va, truc va, tuc xa
luc va » duc va, loc va

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ((ky lang) or (ky dang)) xa hoi. hieu van nam ((tuc va) or (luc va)) dan vai cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ((ky lang) OR (ky dang)) xa hoi. hieu van nam ((tuc va) OR (luc va)) dan vai cau tren.
• Adding a wildcard symbol may retrieve word variants: te sach ((ky lang) or (ky dang)) xa hoi. hieu van nam ((tuc va) or (luc va)) dan vai cau tren*.