Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
van thanh » ban thanh, van tuan
cau tren » cu tren, dau tren, cau treo
thanh vi » hanh vi, thanh va, thanh ve
ve chao » ve chat, ve cham, ve cho
hieu ve » hieu va, hieu van
ty lang » tay lang, ty hang, tu lang
ca tren » cu tren, la tren, co tren
xu van » tu van, vu van, su van

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuoc sach ((ty lang) OR (ty xang)) xa hoi. hieu ve chao xu van thanh vi ((cau tren) or (ca tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuoc sach ((ty lang) OR (ty xang)) xa hoi. hieu ve chao xu van thanh vi ((cau tren) OR (ca tren)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuoc sach ((ty lang) OR (ty xang)) xa hoi. hieu ve chao xu van thanh vi ((cau tren) or (ca tren))".
• Adding a wildcard symbol may retrieve word variants: thuoc sach ((ty lang) OR (ty xang)) xa hoi. hieu ve chao xu van thanh vi ((cau tren) or (ca tren))*.