Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
tay lang » tai lang, tay tang, tay quang
thuc van » thuc vat, thuc dan, thuc va
van hanh » van thanh, ban hanh, van anh
y lang » o lang, _ lang, yen lang
ve tai » te tai, de tai, le tai
vi cua » vai cua, di cua
cua te » cua tu

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 ((y lang) OR (tay lang)) xa hoi. hieu ((ve tai) or (va cac)) thuc van hanh vi cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ((y lang) OR (tay lang)) xa hoi. hieu ((ve tai) OR (va cac)) thuc van hanh vi cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ((y lang) OR (tay lang)) xa hoi. hieu ((ve tai) or (va cac)) thuc van hanh vi cua te".
• Adding a wildcard symbol may retrieve word variants: thu sach ((y lang) OR (tay lang)) xa hoi. hieu ((ve tai) or (va cac)) thuc van hanh vi cua te*.